I've been using KDE for awhile, and just installed Gnome to try it out. I have a couple questions about running the two together.

I have some icons/links to applications in /home/user/Desktop created by KDE. I want to keep the links, but only when I use KDE. In other words, when I'm using Gnome, I don't want them on my desktop. Is there any alternative folder for KDE to use, or something like that?

Also, where is the Gnome autostart folder? Does it even have one? If it doesn't, how do I make scripts start up automatically?

One more question, when I download background wallpapers with the Gnome Art Manager, where does it save them to? Edit: Nevermind on this one, I found it : /usr/share/pixmaps/backgrounds

For starting scripts, have a look at gnome-session-properties.

Also, that might fix the first issue: create KDE-Desktop and GNOME-Desktop in your home folder, and have ~/Desktop symlink to the right one. It should be simple to do with a small script running at the start of the session. It should probably run before nautilus. I'm not sure what it should run before in KDE, so just run it first