No problem, just connect and make sure Bios boot priority set to Windows 7 HDD.. If it was setup in the prefered manner where C = OS + Programs and D = All your generated data/files. You would be able to reformat the "C" drive and reclaim the spcae used by the OLD OS and programs.
The new system arrives from Dell on 3/1/2012. I will boot it up check it out and then connect the old drive. Since it is a brand new system the BIOS should already be correct, unless it "thinks too much".
pw(son of CWO IV)