Video capture board technology changes rapidly. It is best to consult your local computer expert for the latest innovations, and for what will work best with your system configuration.
PASCO offers the SE-7475B USB-to-RCA converter, which works with any analog video source with RCA plugs. Although inexpensive and easy to install video capture port, being a USB 1.1 device, it will only render in 320x240 resolution and occasionally drop frames.
For higher end video you will want to capture in one of the popular digital video formats (DV, miniDV, or Digital8), which will require an OHCI-compliant IEEE 1394 adapter.