Choosing a motherboard

[tmcallaghan-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org (Tim Callaghan)]

I'm looking to build a new system with 8GB RAM and a Q9550 CPU (quad
core).  I'm going to use a swappable SATA hard drive so I can have the
machine running 1 or more linux distrubutions plus various microsoft
OSs, one at a time.  I do not want to be using virtualization as I/O
is very important for testing in this lab environment.

My main question/concern is selecting a motherboard that will be fully
compatible with the distributions I need to run.  I'm certainly going
to be running Fedora Core 9, Oracle Unbreakable Linux, Red Hat and
others.  How do I choose the motherboard so that I don't have issues
getting the onboard USB2.0, audio, video & ethernet working?

I don't need high end graphics, I was planning on going with embedded
video.  Functioning audio is not a requirement but a nice to have.

Any recommendations as to where I can look on the web (the distro
sites seems to have little if any compatibility information and most
of it is regarding HP/Dell, not for a custom system build) or what you
know will work would be greatly appreciated.

-Tim Callaghan