OK, it should be safe to remove/purge Vuze and pgl
pgl .. as that was added with from a PPA, the easiest way would be to use ppa-purge to remove all changes made by adding that PPA:
sudo apt-get install ppa-purge
sudo ppa-purge ppa:jre-phoenix/ppa
sudo apt-get remove --purge vuze
then you can remove any orphaned dependencies with:
BE CAREFUL with that last command .. read what's going to be removed BEFORE accepting the changes, and make sure it's not going to remove anything you need.
Though it IS possible to remove compiz (as long as you aren't going to use Unity or Unity 2D) .. I wouldn't advise it, unless you know what you're doing .. it will definately take Unity and Unity 2D with it, and also the ubuntu-desktop meta package.
I *gather* it's safe as long as you have the gnome shell and gnome-session-fallback installed (as they use Mutter), but I've never tried .. so on your head be it
I'm also not going to give instructions how to do it .. as I don't post things I'm not sure are safe .. but you can take a look here if you wish:http://askubuntu.com/questions/73610/since-ive-moved-to-the-gnome-shell-is-it-safe-to-remove-compiz
As I said .. it's on your head if things go wrong .. personally I'd advise you to leave it alone, if you're using the Gnome desktop, it shouldn't be using any system resources anyway AFAIK.