Turns out Parallels 5.0.9344 doesn't really play nice in the Mac OS 10.6.4 environment. It's hogging memory, so... give it less memory. It has to be physically restricted.
Parallels preferences: Total memory allocated: Manual: 1456 Mb VM Configuration: General: 1Gb memory (I have 4Gb total memory) Options: Optimization: UNcheck Adaptive Hypervisor UNcheck autocompress CHECK Tune Windows for Speed Optimize performance for Mac OS X applications Options: Shared Applications: UNcheck Share Windows Applications with OS X UNcheck Share Mac OS X Applications with Windows Hardware: Video: Maximized video memory (256Mb on this MacBook Pro). Removed my Parallels VM folder from Spotlight.
I'm a bit miffed about the product's crappy support. I had to rely on other users discovered solutions to resolve a serious problem that affects many users.