I use a player called RandomMP3. It starts at a random place in a given folder (drive) and avoids playing the same song before all have played by keeping track of what it has already played.
I have a 20 gig drive about 75% full of jazz and another 20 gig drive 90% full with other music. I keep the unused drive in my glove box. If I want to go from one kind of music to another, I just switch drives.
The computer boots and starts playing music without repeating. That's how I like it. I understand that most people will want to select what they want to hear. I like every mp3 on both drives, so random works for me.