I have a dell laptop also.(600M)
I have stayed away from fedora core 3, because I had the same problem you had.
I really enjoy FC2 as solo OS on my P2 desktop, but I am really gun shy about putting into a dual boot configuration.
If you really want FC3 bad enough you could always install as solo OS and use wine to run your windows programs. ( I myself can not. I have a few custom apps for work that won't work with wine.)
here is a thread from here:
I searched for fc3 and win xp dual boot, but only really got info on FC2.