yes, but you would need ot run a windows xp repair install and then put in a new windows xp key when the computer starts up for the first time, for this key you can use anything, a retail key an oem or an upgrade, all will work for this activation. you do not need to do a clean install, i do this everyday, it is my job, lol, also, if your smart you could activate over the phone with your old key and get put on to a person and say "hi this is mr x from blah blah computer shop, i have just replaced the motherboard in this machine and i need this copy of windows to be activated, then say oit has not been used on any other machine ect ect ect" and they will give you a new key , works a charm.
yup hdds don't really like being transplanted... they have separation anxiety from their old computers, and generally don't get along with new components and drivers and such. however, as previously mentioned, wiping it will make it essentially a brand new hdd and you should be good.
just don't forget to back up what you need [/bad experiences]
a repair install is designewd for this kind of thing, lol, what it does is it goes through and basically re-installs all the subsystems and everythign according to its surrounds, you do not need to re-install windows again, there is no need for it, it just creates excess hassel and amongst other things you don't need to back up because it doesnt remove ANY of YOUR data.
yeah, i actually missed your post earlier; i tried to do this one time, only i had sp2 installed and i only had a sp1 disk, so when i repaired it, my windows went REALLY wonky... that was my fault tho for being dumb, i guess. idk. it was quite weird. well, regardless, chances are the hdd WON'T work without tweaking, whether or not you wipe is up to you. rammedstein does seem to know what he's talking about, i think i'll take his advice for my next build.