I got exactly the same problem om a ACER aspire.
I have tried reinstalling WIN7 severaltimes, after deletting the partitions on HD. Formatting the HD, but hangs same place.
But then I installed on same HD, but on another PC and then WIN7 started, on this PC. But when moving the HD to the ACER - same problem.
Then I tried to repair the MBR with EasyDCD, but same problem...
I think it has something to do with the BIOS. But since I cannot start windows I cannot flash the BIOS :-(