Autodesk changed their interface in 2009 at the mandate of Microsoft who told developers that to be "Windows Certified" they needed to adopt the ribbon interface. If you want to return to the menubar system that LT98 had you can just type MENUBAR at the command line and set it to (1). You can then dismiss the ribbon by typing RIBBONCLOSE.
Having said that I would SERIOUSLY recommend you try to adopt the new interface as this is the standard interface for all Windows Certified applications.
I've attached some screenshots of the ribbon. Ribbon1 is what the interface is supposed to look like. Ribbon2 is what it will look like with an UNDOCKED ribbon. You can grab it and pull it to the top of your screen to dock it (as seen with the red arrow). If your screen has other issues please post a screenshot of it and we can make some recommendations.