At a previous job I worked with some equipment and software from Canopus (
www.canopus.us). This is a few years ago now, but the kit came with a VGA card (in case yours didn't have the right kind of muscle), the appropriate software for capturing and editing, a capture card, and a breakout box. It required a pretty speedy harddisk, and plenty of harddisk space.
The card may not have had the muscle of something from ATI or nVidia, but it was better than what came with the Dells we had. The software was usable, once you got used to it. It was a little quirky, but it allowed you to use the video from one clip and the audio from another, allowed the importation of other image and audio sources (gif, wav), and could provide transitions.
The capture card was installed in a PCI slot, and the breakout box could be attached to the card externally or internally by mounting it in a 5.25 in drive bay. The box had connectors for S-video, RCA (including composite video), optical, and FireWire.
Check out
http://www.canopus.us/US/products/index ... meuser.asp.