I think that Google Desktop, iTunes (with a large library), Chrome with a massively sucking page (because the page routinely freezes Firefox, and in Chrome I can hope it'll only freeze the tab, and in any case Chrome isn't my primary browser), Firefox with a massive ton of tabs, and (previously) Skype (before I stopped it from autolaunching) and also Trillian, in quick succession, is enough to unnerve even a healthy computer. So I try not to do it. Sometimes I forget. Occasions when I forget are often followed by system suck.

I'm using AVG and SpyBot, and they haven't found anything untoward besides your standard tracking cookies.

He is a multicore machine, and I may take him somewhere to get all his bits and bobs checked out for my general peace of mind.

And now the I know that he sees the whole 750g during startup, but not after loading windows, I'm starting to suspect that I did something Excessively Clever when partitioning, and then didn't finish making the other partition, or else Something Weird Happened.