Hi Martin,
Well I personally think everyone should be giving linux a go, and I know its not for everyone. I do feel though that Ubuntu, in particular, is great for anyone who does not want to know about the internals of their computer. It works and has most software setup by default.. though I think more works needs to be done to make the installation of more sophisticated tasks easier.
I'm unsure about your audio hardware though- that could be trick and so could the software, but we can always try and get around that.
I'd actually suggest, as you said, to try a live dvd first - they are quite good but a bit slow to load and run but good to give an operating system a go. You can get it from:
http://www.ubuntu.com/getubuntu/download - choose the Ubuntu 8.04 LTS Desktop Edition.
Let me know how you get on and we can see what happens.