I sing in church(not noisy clubs) and need quality...

[madjim- with the Lord]

Philly,
To get the best quality sound I recommend Hoster (or Hoster light).
http://www.mtu.com/basics/karaoke-hoster.htm (Hoster will also make handling your tracks a breeze, NO DISC!)
Import your disc into Hoster selecting the highest samle rate (192k). This high sample rate gives you the best sound possible and alows Hoster to raise or lower the key with very little change in the track.

Who the track was recorded by (what brand) is a factor that is beyond anybody's control so you will find a track on occasion that just doesn't sound good when the key is changed. This is rare.

I Hope This Helps!

Jim