upgrading windows 2000 to windows xp

I recently bought a Dell laptop that has windows 2000 professional installed on it. The hard dive is in two partitions. I installed windows xp, but its on the same partition as 2000. The second partition didn’t have enough room on it. I need to get get rid of the partitions and start over, but need help. There is an internal Dell wireless on this computer, and I have no driver disk. If I do a complete reformat, will I have to replace the wireless card?