Worth trying again to be honest. 7 is pretty good and is getting positive comments from everyone that tries it. Few things to try;
Can you download it again, or create the ISO?
If you've got 2 sticks or RAM in your machine or more try installing with just one stick , and if the loop continues then swap stick and try again.
You did mention you were downloading the 64bit version. Can you check if all 64bit version drivers are available, if not that may be the isssue.