I got past welcome screen but PC locked inmmediately after and dumped a blue screen with WIN32K.SYS problem.
I have the same issue of WIN32K.SYS blue screens shortly after starting up. I'm happy though for you guys to try and offer me a solution 
I tried running the Supporttool.exe in Safe Mode as mentioned by Gary A (nikki605) above. Kicked it off at midnight and it was still clocking 100% cpu at 8am - is this normal? I suspected not so cancelled it. I did spot that it had created the BDSP zip on my desktop though so I've loaded that to RapidShare.
I'm running Win XP Pro SP2 on an AMD Athlon XP2500+with 1GB of RAM.
I installed BitDefender IS 2012 as a first time user (having left McAfee) following good reviews of BitDefender.
Hopefully someone can help but let me know if you have more instructions and I'll be happy to try 