Hi, mariner.
Sorry it's taken me so long to get back to this.
As I intimated in my most recent message, I'm not quite sure what to suggest with respect to the application SP1 to your W2K installation.  If you decided to go ahead with it, I hope things worked out well.
I wanted to at least get the information about those registry edits to you this morning.
First of all, I strongly recommend the use of regedt32.exe for actual editing of the W2K registry.  I use regedit.exe frequently for doing "research", looking stuff up in the registry.  As I said before, the only time I would use it for actual registry editing would be when there's a corrupted value or key in the registry which doesn't show up when viewing the registry with regedt32.exe.  I've seen cases of this documented at reputable sites, but I've never seen it personally.
Just a bit of information about the use of regedt32.exe, in case it seems as strange to you as it did to me when I first saw it...
Creation of a new value:  Highlight the key location in which you wish to place the value in the left pane of regedt32.  In the Edit menu, choose Add Value.  A small Add Value dialog box will appear.  Enter the exact name of the value in the top field.  Choose the data type from the drop-down list in the second field.  The type of data you are adding will determine the format of the next dialog box you will see.  You enter the actual value of the data in this box.  It is important to pay attention to the radio button selectors at the bottom of some dialogs to be sure that you enter the data in the correct format, for instance -- bin / hex / decimal.
Editing a value:  Locate the value you wish to edit in the right pane of regedt32, and double-click on it.  You will get a dialog box which lets you edit the value.  When doing this, take note of the radio button selectors (as mentioned above) to be sure that you are entering the data in the correct format.  Unfortunately, many people who publish tweaks or hacks aren't very specific about the format of the data to be entered.  (Oftentimes you can tell by examination and doing a little thinking.  Obviously it doesn't matter much which format you're using if the value is zero or one.)
Now, about the two registry keys we've been discussing:
The "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer" key to which I referred is the site at which you can choose to add a vlue which is supposed to cause the Desktop and Taskbar to run in their own thread.  Then each instance of Explorer that gets started gets its own thread, also.  It is presumed that this makes a desktop crash unlikely to end an instance of Explorer, and vice versa.  This may, or may not, improve the stability of your Desktop.  If it does, then that should be a positive thing for all apps.  Everyone I know who has used it has liked it.  It also seems to make the Desktop more responsive on most systems.  If you want to try this, go to the key and highlight it in the left pane.  Use Edit | Add Value to add a REG_DWORD with the name "DesktopProcess" (no quotes) with a value of "1" (one).  (Note: place this in the Explorer folder, NOT in one of its subfolders.)
The value of the AllowWindowReuse entry in the For "HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main" key is supposed to be controlled by a setting in the Advanced tab of the Internet Explorer Tools | Internet Options dialog.  There is a checkbox setting there called "Reuse windows for launching shortcuts".  If you UNcheck the box and hit the Apply button, the value for AllowWindowReuse should change to "0" (zero).  That setting should provide some isolation among Internet Explorer threads so that, when one crashes, the others don't come tumbling down.  This is what I was trying to accomplish when I suggested the Ctrl-N keyboard shortcut for opening new IE windows, but it's less certain just what any of this accomplishes since the advent of IE 5.x, which evidently exerts more control over whether or not new threads are started based upon various facets of the system state / resources.  
BTW, I was using the term "process" rather vaguely and imprecisely in that earlier message.  I should have been using the term "thread".  I'm sorry about any confusion that caused.  Too many operating systems and too many sets of nomenclature clutter my tiny, old mind.  I was an AIX guy until a year ago.  Before that it was CP/M and some DOS, Apple DOS / ProDOS, and... Well, you get the idea.  I've never been an IT guy, anyway.  Just a medical physics guy who had to use computers.
A couple of notes about the stability of Internet Explorer, in particular.
There's no doubt that with all of the hoops that Microsoft has this browser jumping through, that there are a LOT of things that can impinge upon its stability.  I would think that Windows File Protection would help prevent adverse changes in file complement from having a great deal of impact on this matter, but I know that the ODBC DLLs are NOT protected by WFP.  I suppose it's possible that there are other exceptions to the protection, too, which may have some effect on IE.  The registry is still pretty vulnerable, and it gets messed with mightily, particularly with multiple browser installations, multiple Java implementations, and stuff like RealPlayer.
There's also the matter of user behavior in browsers and the effect of said behavior on stability.  I have seen identically configured systems behave very differently in this respect.  A close friend of mine who seems to average about two browser crashes per minute uses her browser this way:  When navigating to where she wants to be on a site, she NEVER lets a page load completely before she clicks on the next link.  She also frequently closes browser windows when the pages they're loading are still in the process of loading.  I've explained to her that she can a) be more patient and allow the loading / applets / whatever on each page to proceed to completion, or b) click on the Stop button on the toolbar to get the page loading process to halt (not always 100% effective when certain types of scripts are running) BEFORE closing the window or clicking on the next link.  When she remembers to do work this way with the browser, it doesn't crash on her.  As for me, I'm old and slow, so I don't have much trouble following my own advice on this matter.  I have had iexplore.exe crashes, but no more than a handful in the 7 months I've been using W2K.  If you're a lightning fast mouse clicker like this friend of mine, you might give the low and slow method a shot just to see if it improves matters.
Beyond this, I'm at a loss.  It's pretty obvious that the experiences that people have with this particular issue are widely varied.  And I don't think even Microsoft, much less anyone else, has a handle on it yet.  There's every chance that some third party software has a lot to do with it, but I'm danged if I can see any absolute correlation.  For instance, I absolutely hate RealPlayer.  Everything about it.  I've tried it on a few systems and found it to be incredibly invasive, destructive, and not a particularly good player, either.  On top of that, it installs spyware!  Sheesh!  I won't use it on any of my systems, and I'm pretty sure it has whacked quite a few PCs.  But it's nearly ubiquitous on line, well, at least at certain types of sites.  And I know people who use it constantly and who say that it doesn't do anything adverse to their systems.  Now I'm one of those guys who seems to almost never see the problems that get widely reported by other people.  I've NEVER had a problem installing a Service Pack, a Service Release, a hotfix, a security patch.  I know people who have had problems with ALL of those types of installations but who never had a single glitch with RealPlayer.  Some people swear by Norton Systemworks, and other people only swear AT it.  Bottom line: it's a strange world that we live in.
I hope it's going better for you today.
Regards,
Jim