I just did a Win 7 Home Premium restore on the Wife's Dell 1764 64 bit laptop. She was taking it out of service and wanted it wiped clean of all her data. For some unknown reason, the restore partition was corrupted and would not work. Thinking that I owned the operating system, I thought that Dell should make something available to me to affect the restore. They told me that I should have made a 'restore' disc when we first bought the computer. However, for a mere $19.95 they would send me a Restore thumb drive. They did and it worked. Maybe this would be a least cost, least hassle option for you?
The Dell part number (at least for the Dell 1764) is 7HV83. The description on the packing slip is 'KIT. SW, W7HP64, USB, WW, MUI, ALL:
Along the way, during the restore, it looked as if all it wanted to do was to 'repair' the operating system. Near the end, it said no issues were found but gave the options to back up data on another thumb drive and then do a total restore. Give Dell a call.
EDIT: I see I missed Pg 2 before making this post. However I did not see how it was that you got back to Win 7?