Dolby 2.0 or Dolby 5.1 downmix?

[neo_sapien]

Given a TV without a 5.1 stereo system and the choice, do you prefer straight Dolby Digital 2.0 audio, or Dolby 5.1 audio downmixed through the DVD Player?

Here is my predicament: I have a Dolby 5.1 computer system which I make DVD rips for, and also a DivX standalone I built for my mom, hooked up to her 27" TV. What I've been doing is one DivX for myself (which is a 5.1 audio track), and one DivX for my mom (which is a Dolby 2.0 audio track, or a VBR MP3 of the 5.1 if a 2.0 isn't present). This is incredibly wasteful, because I have to rip every DVD twice. Should I trust the 5.1 downmix of PowerDVD 4 XP to Dolby Surround 2 speakers?

Thanks :)

[Taric25]

Although 2 rips may be take more time, the Dolby 2.0 is better mixed (it was taken from a PCM stream rather than a lossy AC3) so it will be higher quality.