The best is to get rid of sudo altogether.
The second best would be to understand sudo, and what it might be used for. The Ubuntu way is not what it might be used for.
(That is not against Ubuntu, i don't care how they do it, and it probably is a distro as good or bad as any other. I only say that using sudo that way doesn't make much sense, and leads to trouble too. There must be a reason all other distributions do it different, or not? I doubt that is the source of your actual problem, but i picked the best option, instead of the second best. That means i use su).
The most short way to say how i do things: i use the Debian defaults. I ain't got much problems, though i don't know much.
If you know why you use sudo ignore my post.
"Failed to suspend session. No kernel support"
No clue, i never suspend, but i would simply try a different kernel, say liquorix. The other option is to search the web for that (until someone can tell you, i can't).
If you still do it in VBox go to -> settings -> system -> processor -> and enable PAE at the bottom of it (wild shots in the dark).
btw: at the very top of this thread you ask about xfce/compiz. It works good for me (but so does gnome...). It is worth a try.
"I am not fine with it, so there is nothing for me to do but stand aside." M.D.
(I usually have a root account I never disabled it until this install).
