I just finally sucked it up on Vista. With all the information, tweaking and some stability issues resolved, I put Vista Premium back on my XPS 410. I used my 1520 as a test bed and have been pretty happy with it. XP has been solid and I'm sure there are reasons to use it, hopefully I won't have to go back. Graphically, Vista is a lot prettier to look at.
Good luck finding your drivers. I was able to get XP Home running very stable on my 1520. Dell was pretty good about updating the availability of XP drivers.