If you are spending a lot of time trying to fix an issue, there may be underlying issues that you haven't seen yet. This happens when people use registry cleaners, etc., and they remove certain (necessary) settings. The whole re-install will take a couple of hours, and you will not only fix your problem, but you will eliminate a bunch of junk around your system. You will feel like you have a new machine. You will have a noticeable speed increase.
The biggest amount of time will be Windows Update, but that could be done overnight, while you're asleep. Back up your data (My documents, downloads, etc.) to another hard drive (usb or internal) and you're good to go.
The choice is to definitely fix the problem in less than a day, or continue to live with this headache until someone figures it out for you. You may find that this topic could go on for weeks as people throw random fixes at the target, hoping to fix the issue.
If he's already an admin, the odds are something is hosed. One way to find out is to create another admin account. If that one works as it should, use that one. If not, zap the machine and do a clean install.