I myself am a complete newbie to Ubuntu/Linux and I had no problems setting up a
dual boot on my computer. I did install Ubuntu on a seperate HD (250gig), and
left XP on the main drive alone other the grub.
Ubuntu to me was easy to setup. I did have to get a new wireless card to work
with ubuntu but found one for $30.00 and could not get it to read dvd, but there
is enough info around that I finally got it going also.

Ubuntu in my opinion was actually easier to install then doing the upgrades from
98 to XP.