Startup problems after changing SATA cables for hard drive and DVD drives

I was planning to install a second hard drive on my XPS410.  I'm running VISTA 32.  The Dell Owners Manual says that hard drives should be connected to SATA0 and SATA1.  The #1 hard drive was connected to SATA0; the DVD in SATA1 (factory install).  I decided to try connecting the DVD to SATA2 so I could connect the new 2nd hard drive to SATA1.

I wanted to test that change before installing the new hard drive.  The system went into Startup Repair and wouldn't come out -  it ran for over an hour. 

Then I shut it down and restored the cables to their original SATA sockets.  Now it still goes into Start-up Repair and won't come out. 

Was there something I should have done in Set-up? Can someone tell me how to restore my original configuration before attempting to install the 2nd hard drive?

I tried to reboot off of the DELL VISTA CD to restore the system.  The DVD works, but the system went back into Start-up Repair.

Grateful for any advice.