Yes, as long as the game has music written for MT-32 it will sound better than the General Midi or Sound Blaster options but not all games that have an MT-32 option were written to use it (see incomplete list at http://en.wikipedia.org/wiki/List_of...computer_games
). Also keep in mind that older MT-32 games did not have a separate driver option for sound effects so in those games you will only get music when using MT-32.
25th anniversary and judgment rites both have MT-32 music (and sound really good played this way) but as I mentioned in my above post there seems to be an issue with the CD release of judgment rites.
Obviously the best results for playing MT-32 games come when using a real MT-32 but thanks to Munt there is a pretty good software approximation available. Munt is built into some custom builds of Dosbox like Daum. All you need is a copy of the MT-32 rom (which for copyright reasons you will need to find yourself) put into the Daum root folder, edit Daum dosbox.conf line "mididevice=default" to "mididevice=mt32" and configure the games options to use MT32. Dont forget to change back "mididevice=" to default when playing non MT-32 games (or use different profiles for each game you run in dosbox).