Of course you can...just put the outputs from your VCR (either Composite or Coaxial, doubt your VCR has S-Video) into your computer directly and record away. How big is determined entirely by what bitrate you choose to encode at. For instance, I recorded ~70 minutes of TV for my wife last night at the highest setting and it was 6.7 gigs. If you are putting this on DVD, I would suggest recording at the highest quality, and the burn software should encode it back down to 90 minutes DVD quality. Start high quality, end lower...otherwise it's garbage in, garbage out.