It wasn't just installing stuff, my computer wouldn't turn on after crashing and I didn't know what was wrong. Turns out my primary hard drive was going bad. Besides, once a friend who knows more about computers than I do (he built my video editing one) tried to install a hard drive on another computer and it crashed within a week.

But anyways, now the problem is that my DV capture box seems unable to recognize a firewire signal from my Canon ZR70 miniDV camera. It never really worked before but I rarely use miniDV so I didn't bother with it. It has always recognized composite and s-video. I figured it needed some drivers or installation but the guy at the store did get it to work once. But doing the same steps the next day would just make it turn off.
It is a Pyro A/V converter from ADS Technologies. I got it in late 2003. There's a analog/digital push button on it. Whenever I press play to turn on capture preview in Vegas, it goes to red indicating analog. But even with only a firewire cable hooked up, pushing it again will turn off preview instead of switching to the digital signal.
The guy at the store seems to think the capture box is not working properly.