Frame and Frontpage... two things you should not be using to build webpages (unless you're building an intranet where things like browsers and users are controllable.)
There are plenty of ways around your problem. If you could place your scrolling content into an div with its overflow set to auto (ie. <div id="content" style="overflow:auto">Scrolling content codes here</div>) Or you could use javascript to move the navigation menu with the page.
However, if you have enough content on your page that you lose sight of the navigation menu, you should probably break up your content into multiple pages.