Recording software not recognizing inputs, maybe a clean reinstall to fix?

I have a bunch of audio recording software, some of which is transferred over from my old PowerBook G4 running Tiger, not all of which is absolutely known to work with Snow Leopard (which I have on my brand new iMac). The rest is known to work with SL, but for some reason isn't recognizing the audio inputs and in some cases, ends up crashing whenever I try to do anything.

My theory is that there may be some sort of conflict with older versions or preferences that transferred over when I used Migration Assistant to set up the new computer last week. I've gone through the system and user libraries and tried to remove all of the preferences files and other things that would have been referenced by older versions of the software, in an attempt to fix this issue, but I've had no luck yet.

I'm wondering if a clean reinstall of SL may be the solution, skipping Migration Assistant and then just copying my important preference files manually?

If that's the case, how would I go about doing the reinstall? I've never done it before.