One of the VHS to DVD boxes is the cheap and cheerful solution; you'll always be able to rip the MPEG-2 files from the DVD and convert them, but the quality will become progressively worse. You could buy an analogue capture card for a PC, but then you have the complexity of capturing the video and converting it into whatever format you want to store it it.
Personally I copied all my old Hi8 tapes onto MiniDV using my old camcorder's analogue inputs, and then captured that by Firewire. It's a fairly low-compression format so doesn't lose much quality over the originals. I believe most Digital-8 camcorders could do direct analogue to digital conversion onto Firewire when playing 8mm and Hi8 tapes, but I'm not aware of any similar capability for VHS.