Apparently you might be able to dl a 64 bit iso now to fix teh 32 to 64 issues people were having. Otherwise here are the directions:
Turn your Digital River Windows 7 upgrade into a bootable DVD:
1.Download oscdimg from SevenForums and extract it to C:Windows\System32 (link below)
2.Open an elevated command prompt by typing cmd.exe in your Vista Search box. When it shows up right click and select run as administrator.
3.Paste the following into the command prompt, be sure to put your username in:
Oscdimg.exe –u2 –bC:\Users\your_username\Desktop\expandedSetup\boo t\etfsboot.com –h C:\Users\your_username\Desktop\expandedSetup C:\7.iso
4.Press enter and wait for your ISO to be made.
5.Burn to a DVD with a burning program and you are ready to go.