Oh boy. That sounds ROUGH! I hope you still have some hair left.
Ok, let's start from the top... Is Parallels tools installed?
!!CAUTION!!
Back-up Before Proceeding
Have you tried re-installing OS X and then installing Parallels first after applying all of the OS X updates?
Alternatively, re-installing OS X, applying OS X updates. Then get BootCamp up and running... Then, go install Parallels and point it at the BootCamp partition. See what stability is like. If it is good, install the rest of your apps.
Also, if you want to upload your crashreporter.log and any panic.log you might have that might assist us.