A normal stand-alone tivo will not function very well without a subscription. If I recall from the 2.0 days it would allow you to time-shift (30 minute cache) and manually setup recordings like a VCR. However, you would not be able to get guide data or schedule any recordings from the guide (since you didn't have a guide).

There are some new TiVo devices coming out from Toshiba and others that have a DVD burner built into the TiVo. You do not HAVE to pay for guide data, but you will only be able to schedule things 3 days in advance. If you pay for the guides, you can do the normal 2 weeks in advance. I may be a tad wrong, but from memory I think that summary is pretty accurate.