I would really start by not using frames. The use of a JavaScript really shouldn't be used in this manner, either. It's supposed to enhance a visitors experience if it's available. If not, the site should still function. I strongly advise that you drop the frames, however.

I don't know if there is a way to redirect a visitor if they don't have a JavaScript enabled browser, but you can redirect a visitor depending on if a function is able to execute though. I'm just not sure how well this would work: If a browser can execute the function, just not over frames, then the redirect test would fail.

This might be useful:

http://www.webmasterworld.com/forum91/887.htm