How are you running games?
How did you play Uru - don't you need to hear people talking and such?
Uru did have quite a lot of music, and no it really hightens the gameplay.

Are you serious???? No sound card? Go buy one, mate!

Hehe its funny that you bring up Mario. As Robyn said in the making of Myst (I'll just quote the whole thing so ppl know what the music idea was about):

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>"We didn't want music interfering with the gameplay, and so we weren't going to put any music in. When we finally did do a couple songs we realised it wasn't an interference; it didn't sound like Super Mario Bros. It seemed to really help the mood of certain places that you were at in the game."
- Robyn Miller, The Making of Myst (included with the original Myst game)<HR></BLOCKQUOTE>

The gathered will tell... Cool I'm one of the gathered!