I've been getting exactly the same problem as this when trying to install
Vista Ultimate from an OEM disc. It stalls between 3-5% through expanding
files. I've also tried upgrading from Windows XP Pro (SP2) and experienced
the same issue- the install does not complete. I've tried reformatting and
repartitioning the drive I'm installing onto (both using the option within
the install interface and also plugging the HDD into a different machine
running Vista for a full format), as well as using alternate install media.
None of this has been successful, and since then my PC (with a fresh install
of WinXP in the interim) will not recognise the HDD unless the WinXP CD is in
the drive. I have yet to try a flat install (will have a crack at it this
evening), though I don't hold out much hope.