PS: I'm cheating anyway - I'm a jscript/cgi/.net newbie just trying to make a few things work! At least with straight html I don't have to cover instances where java is not enabled! ;-)
There are a lot of ways to do this. None are particularly elegant. One method is to use the "onLoad" event on the body tag. It has been a while. Seems like it goes something like this (my javascript might be a bit rusty here)
That will prevent your frameset document from being "framed". Note, change the 'index.html' in the window.open to whatever the document is that contains your frameset.
<body onLoad="if (self != top) { window.open('/index.html','_top','') }">