upgraded to ubuntu 11.10 can't log in under ubuntu

Once I upgraded I was presented with a choice of different ways to log in. The one that says ubuntu would not allow me to log in a session. One that said gnome classic did allow me to log in but most everything about my desktop, applications, Internet appearances, some of my programs, etc. had changed or, even, were not available. For example; I had my screen saver set to scroll through my pictures file. When I upgraded, not only wouldn't it work but it said it wasn't available. I even went to the software sight and downloaded a screen saver for this purpose. I set it up but my computer denied that my picture folder existed. Yet I can still pull the folder up. There are other frustrating changes also. I was wondering if I did something wrong or if this is common malady and what can be done.