Upgrading (custom) to Windows 7, Used Windows Easy Transfer, and cannot complete because HD does not have enough disk space

I have an Inspiron 530 which used Vista. I decided to upgrade to Windows 7. I prepared by using Belarc Advisor to summarize my system. Next I used the Windows 7 Upgrade Advisor Report to check compatibility. Finally I used the Upgrading from Windows Vista to Windows 7 (custom Installation) document, which I think I got from the Dell support area. The report before starting the process showed the C: (NTFS on drive 0) was 489.32 GB with 333.61 free. There are 2 other partitions on the drive 0 for the Recovery and for OEM. I understand that Windows 7 with a 64 bit installation requires 20 GB, according to Microsoft. Per the Upgrade instruction document, I backed up my settings and documents, etc. with Windows Easy Transfer before doing the installation and that file was backed up to an external HD. The installation of Windows sent just fine. The next step is to transfer back to the C: drive for the "Windows Easy Tranfer-Items from old computer.MIG." Partially through that process, I got the warning "There isn't enough disk space to transfer your files and settings. Disk space is low. Are you sure you want to continue to save your Easy Transfer File here?" When I look at the file size that was created and saved to my external hard drive it gives the size at 708,878,222KB. I notice that the Windows.old folder, that was created at the time of the upgrade presumably as a safety net of sorts, is 107 GB. I do not know if I can transfer that to another hard drive and free up enough space for the documents and settings, as well as the programs that I need to re-install. What happened and what can I do now? I am right in the middle of the process.