Originally posted by: TheStu
WelshBloke: I have never run into compatibility issues when running Perian, it really is a great app to get, it is free and works as advertised, what more does one need? As for your Dock issues, after about a year or so of owning a Mac I moved the Dock to the left side of my screen (mounted vertically). It takes up less space, and you get all your vertical pixels back. I realize that it is a hard adjustment to make sense you are used to having your applications listed on the bottom from Windows, but give it a whirl.
As for your Applications folder issues... When you open a Finder window, you have items listed in the sidebar on the left, organized into groups. Devices on top, then Places, then Search For. Within Places you have by default, Desktop, Home (or whatever you called it), Applications, and Documents I believe.
What it sounds like you did was drag the Applications entry from the sidebar. Think of the sidebar as a bookmarks or shortcuts bar, you can drag items in and out and they are just links, not the actual item. To get at your Applications folder again and put it in both your Dock (place it to the right of the divider, immediately to the left of the Trash Can, that is where folders go) and your sidebar again, just go to your OS Drive(listed under Devices in the sidebar). By default it is called Macintosh HD, but you may have renamed it. Click this and right there is your Applications folder. Do not move this or anything, just drag it to the sidebar to the 'Places' area, and then drag it again to the Dock. Not immediately intuitive I suppose now that I have explained it, but what is intuitive to some is next to impossible for others.
I highly recommend experimenting around with the OS, and reading my Guide at the top if you haven't already. The Guide is a little out of date, and I meant to do a re-write when Leopard came out, but I may wait until I get my new MacBook Pro with Snow Leopard.