I dunno much either. I Show U HD is available on the App store and I think Quicktime wil record if you're desperate (low framerate though)
as for PC gaming, I couldn't say. I tried VMWare Fusion and it seemed to do okay as long as the game wasn't too challenging technically, eg don't expect to be running the PC version of Diablo III on your Mac. Parallels should be okay. I don't have a preference either way
Of course, you could install Boot Camp, but that's too esoteric for me and too able for me to screw it up, ie not goof-proof. Whatever solution, you'd probably need a copy of Windows Xp with service pack 3 or Windows 7
as well. Crossover works fine, but only with stuff from 1999 or earlier, it's goof-proof, easy to setup and run
your mileage may vary.....
John b