When trying to install windows xp professional on my PC it decides to turn off just as I am about to start installation. I have AMD athlon 3200, 2gb ram, WD raptor 74gb sata + maxtor 80gb hard drives, Plextor DVD/RW drive, sony DVD drive. Any help would be greeted with a thousand thanks.

Does this happen all the time ?

At what stage of the install does it happen ?

Yes it does and it happens right as I'm about to hit enter to proceed to install.

Try unhooking all the drives except the hard drive and dvd-rom... then give it another try while unhooked

I've managed to get to about 80% and it says it can not copy diskdump something or other and then decides to turn off.

Sounds like it maybe an insecure connection some where.
Time to crack your box and reseat ALL connections. e.g. RAM, PSU, DVD, etc
WHen reseating blowing out the connection with compressed air helps to remove built dust.

Hope this helps.