For Windows you should only be looking at Snapstream's Beyond TV or SageTV in my opinion. Maybe Meedio (formerly MyHTPC, now commercial).

Nothing (software app) from a hardware company is any good, including the software that ships with the ATI products - especially the horrible Gemstar Guide+. You can use any number of capture devices with the above software. I'd recommend using something with hardware-based encoding. The only product from ATI I can recommend is the TV Wonder Elite (brand new, comes with a remote). Make sure it will work with the above applications - I'm not sure if they've verified that yet. Otherwise you should probably stick with a Hauppauge card like WinTV250 or something - lots of people have them and they're well supported by the applications above.

Any other solution running Windows is nothing like a TiVo (I suppose you could also try your hand at Windows MCE, as it's getting better). You'd be very disappointed by Freevo and/or MythTV if you were looking for anything like TiVo as well. At least that's my opinion after breifly setting up and running MythTV and reading about and viewing shots of Freevo interfaces/requirements online.

Bruno