I'm convinced all the previous problems with faulty install of 64bit version W7 were because of a faulty burning program, Roxio 9, which states "verified", but disc is corrupted.
PLEASE use CD BurnerXP which is free, fast, simple, rapid and reliable!!!
Roxio seems to be causing more and more incompatibilites - similar to an antivirus program which shall remain nameless, . A few weeks ago I came across a system where the optical drive disappeared from My Computer. Another tech said to uninstall Roxio .. that cured it. Was a new one on me.
I also used Nero 8 to burn both the 32 bit and 64 bit versions of Win 7 and had no problems with either disc.. I used Roxio a long time ago (probably 4 years ago now) and hated it from the second I finished installing it.. I've never had any problems with Nero though..