Thanks for the reply Arc..
couple of things...firstly, I'm having problems installing SP1 by any of the ways suggested, burning the iso, tried mounting it (not literally!! lol). DL'ed from MSDN, DL'ed through updates...all failed. Tried the System Readiness Tool as well.. any ideas?
next is Memtest, it's prob very easy but how do I a) select how many passes it does? when I tried it, it was up to 10 I think and still going! and b) How do I get the info from memtest into a format where I can post it?