That makes absolutely no sense. There is almost no difference between Ultimate and Home Premium. I have systems running both and there is no reason to spend extra for ultimate unless you have to have one of the few features it has the Home Premium doesn't.
I recommend going with home premium 64bit like gt7sanremo posted.
I only have experience with vista home, not ultimate. I have however owned both home and pro editions of xp and without a doubt pro edition is a world of difference for the better. With home edition xp, it had many small problems. Had trouble just networking. It seemed to lag a lot. It ran ok but it was nothing to go praising. One day it just pushed me over the edge and everything went wrong. I got a cracked version of xp pro and installed that. From that moment on, I have never looked back at home edition. My networking problems were just gone simply from switching over to pro. Only difference was home to pro. All setup exactly the same way. I used to lag on the internet with multiple pages with home edition. With pro that was just gone. No lag, just worked flawless. I used to have trouble connecting to servers for games with home edition but with pro it was just all the sudden worked.
My laptop I have now, came with the upgrade to vista home edition upon its release. I all the sudden had a very similar experience as with home edition xp. Vista actually took 5 minutes to boot up to the desktop. I got a core duo system, 2 gigs of memory. Plenty to be able to run it. Wouldnt even network with xp. Just down right wouldnt find anything. I played around with it for a few hours and ended up at the end of the day going back to xp pro. Problems solved again. Windows boots up in 30 seconds max to desktop. Everything once again works flawless.
That right there was my experience with the "home editions". Hopefully now you can understand why I made my first post to begin with. SImply going with pro solved my problems without me doing anything. XP Pro FTMFW