I'm just a user, not a support person, but I went through a period like this, too.
I basically had to start completely over, but starting with backing up all the Parallel files from my MBP to my XP desktop, doing a complete housecleaning of Parallels (removing), using the Parallels uninstall tool, and trashing everything left in Applications and Documents. So, then I just left things alone, no new installs, letting my MBP run without any "banging around" for several days (ran some Utilities, etc.). Then installed Parallels, again. This seemed to finally clear things up. I was even able to open up my earlier documents that I had backed up on the desktop. There's some additional info in this support article: http://kb.parallels.com/en/4790 There's actually a lot of stuff in that article area.
I've read that some MBP just seem to be incompatible with Parallels, and I thought I had one of those. It was that bad. I have one of the early MBPs. Now, I'm trying to get compression to work, but it has been running fine. Slow, but fine. Good luck.
Last edited: Apr 24, 2008