you dont have to wipe everythng jus put the XP install disc in and it will replace your 98 install. i did this with my girlfriends family pc and it worked a treat.
genesis, go search google for stardock. they make some really cool skinning programs for XP. custom cursors, animated ones, new desktops. heres some pics of mine at the moment:
click the pics for the big version.
As you can see, i took screen shots as i went along they do free and deluxe versions, but you can get the deluxe version for free, if you catch my meaning
If you do upgrade an older PC from 98, its often worth while downloading some of the drivers specifically for your components, such as network and graphics, otherwise if the XP install doesnt recognise them, then you have no network or decent screen res to solve the problems.
well mine got xp'd over the last 2 days and it seems to be fine now! had a battle with norton antivirus though, damn stupid thing, sorted i think now. got to reinstall some stuff then it's back to normal! yay! i can use itunes!