I found
http://www.togaware.com/linux/survivor/ helpfull with dealing with Debian, even if it is for Desktop stuff.
For a server just setup Debian Stable and thats it. I don't do much in the way of web developement, but from what I've heard Debian has one of the better Apache + supported software setups aviable.
The most difficult thing to deal with with Debian, in my experiance, is working my head around to learn to live with the apt-get/dpkg stuff. (originally learned Linux with Redhat, but moved to Slackware, which I liked, but with a entirely different philosophy) It's a very dominate part of the system and everything is geared toward making it work in the system.
But it ensures that everything actually works as the package maintainers intended, which ultimately saves a lot of work for you. With a very complex website the 'software stack' can get very deep. You have php version this, php-mod version that, apache version y, mysql database version x, kernel version x.y.z, built by gcc compiler a, and this or that version 2.0, and maybe a half of dozen other packages and php modules, or whatever bits of code you pull from whatever library.
You do a upgrade and any of those changes create a incompatability then at least a part of your website is hosed.
Then when you take into account that by compiling your own software from code, with different optimizations, make options, dependancies, you can be affecting any of those before mentioned packages in any hundred numbers of ways.
So you have all these variables, maybe hundreds of them, and any single one of them, or unlikely combination of them, can potentionally cause you greif. Weither it's bad programming choices on your own, or bad make/dependancies combinations/choices, or software bugs, or anything...
That's why that although I think Gentoo does a lot of stuff that is cool, I can't imagine that quality control among the actual software and software packages can ever be that great.
With Debian Stable your dealing with a relatively static enviroment. If you have a problem or need to file a bug report you simply have to tell your problem, you attemtps to fix it/troubleshoot it, etc, and that your using software x, y, and z from Debian stable. The Debian developer in charge of that actual peice of software would know the dependancies, the make options, the patches applied, by default. And other users are going to be using the same exact software as you do so that when looking for help it's easier that way.
Also when you do upgrades you know that it would have to be done for a reason. When you have to upgrade a package you know that it's not because company X released a new minor version, but most likely because there was a serious bug or security flaw that has been fixed.
That way once you know that something works.. it's going to keep on working for the next few years. You get to spend your time improving it or working on something else rather then having to put out fires.
That's not to say that your not going to find bugs.. all software has bugs.. but at least your bugs will be consistant with other people's and work arounds can be shared.
It's a rigid system, but it's well thought out. You have details like 'alternatives' for selecting defaults between programs that have similar functionality.. you have the ability to rebuild packages from source if your realy realy have to for whatever reason. You can pull down packages from testing or sid if you need the latest and greatest features for whatever reason, but only upgrading the packages that are needed to get that to work and leaving the rest of the system untouched. Things like that.