People around here like the Canopus ADVC-100. It'll change your analog video into DV video - the same format used by DV camcorders. So it is an ideal fit for Video Factory.
Plan on adding a few extra $$$ on top of the price of an ADVC-100 if you don't already own a Firewire card - you'll need one and it isn't included.
Unlike many budget devices, the Canopus ADVC-100 captures both audio and video and does not rely on your sound card. This ensures accurate sync which can be a problem with budget cards.
However, it requires a fast system to work well and since the video is uncompressed, a lot of hard drive space is a must. TV tuner cards can also suffer from the sync problems mentioned above so a good sound card is definitely a plus.
I'd avoid anything that connects through USB.
If your system is so-so and requires upgrades, a Canopus ADVC-100 may actually be cheaper so weigh your options carefully.