I bought a dazzle capture card, its kind of confusing but not too bad.
Basically the capture card is a little box that plugs into your usb (install cd)
then you plug your xbox into it and it comes up on your computer.
(the tricky thing is)
you want to play on your tv, but the yellow cord is going into the dazzle. so you have to buy an extra splitter so you can still plug it in the dazzle and the tv. (this is illustrated well on youtube)
I havent been using it tho because it makes a dvd file and im not sure if i can edit it.
I have been using my little flip camera and the quality has been pretty good although its not a direct capture.