Usually, video ports on a video card or motherboard are out only. You would need a capture card, or external box to get VHS video digitized into your computer.
For VHS tapes, I would recommend getting a Hauppauge HD-PVR available here: http://www.hauppauge.com/site/products/data_hdpvr.html
It would save you a lot of headaches and make your job much easier.
If you'd like specifics: the HD-PVR has component inputs with optical audio, along with S-video and composite connections.
I've used it to capture many VHS tapes, and never had a problem.
Good luck!