I guess it would depend on What Kind of money you want to spend and if you want to go digital Or Analog...I use a Cheapo ATI TV Wonder that was about $30 and I get fairly good Quality from good VHS Tapes and when useing Genaric drivers It Can capture at higher than DVD Resolutions...Go Here:
http://dvguide.sharbor.com/head-to-head/ there are some good comparisons of different capture cards...