vista upgrade failed. big time!!!

the installation went ok, all installed, then came the screen please wait
vista is starting up for the first time. then a window appeared that it had
failed and the screen turned into hibernate mode. i rebooted and it siad it
was going to roll back to the previous windows and that failed now when i
start windows up the normal boot process happens but this 'dos ' window
appears with the following .
at the top it is-
administrator:x:$windows.~bt\windows\system32\cmd. exe
then
microsoft windows[version6.0.000 ] etc
then
X:\WINDOWS.~BT\WINDOWS\SYSTEM32>THEN THE CURSOR BLINKING

please help cant start it cant restore or anything, and the killer is the
start up process doesn't get to the page where i can start the dell pmb ( i
think ) to restore the computer from the hidden partition put there by dell.