I've got a TV Tuner in my laptop running on Media Center Edition 2005. It works perfectly fine but not as good as I thought.

I know that Tivo lets you rewind something that you have not seen already and fastforward to something that you haven't seen (Except LIVE ofcourse). I though this is the way Media Center would run, it doesn't though.

The way Media Center runs, is it keeps like a timeline of all of the channels you have watched and for how long.
EXAMPLE: If I turn on channel 5 for twenty minutes and watch that and then switch to channel 33 for five minutes and then to channel 75 for five minutes, when I try to rewind, it just goes in backwards order of ONLY what I have watched. So when I rewind it, it would go for five minutes of 75, five minutes of 33, and then back to twenty minutes of channel 5.

My question is are there any alternatives to Media Center that will let you watch TV from the coaxial cable in my capture card and actually use it like a Tivo and be able to rewind and fastforward to TV programs that I have not viewed yet?

In order to get the TIVO effect of watching one channel while recording another one, you would need to have a TV Tuner card for your computer that has a dual-tuner. Basically it would have to coaxiel inputs on the card that your plug both into your tv cable. This would allow it to record on 2 stations (aka watch 1, also record on another).

You can try Media portal (open source ) but it runs under windows as well.
So you still need a windows version (home , pro or Media center it doens't mater).

You can find more information on their site http://sourceforge.net/projects/mediaportal/
I have never tried it yet, since I have now Digital TV over DSL .
Maybe I try this with a satelite dish (but I haven't one now).

The software can work with multiple tuners and several cards are supported.