Are you using Norton. Back in the old days, "disabling" that was sometimes insufficient. You had to uninstall. Then you could later reinstall Norton after installing.
Also, try right clicking the install program and choose RunAsAdministrator.
Here is another thing that might be best of all. Create a new Administrative user. Login as that user, and do the install. Since the new user gets IE set up to defaults, as well as other things set to defaults, that might be the best solution for you.