Oh, okay, it's very easy.

Click start>Admin tools>event viewer
Now, what you are looking for would be in Applications or System, and errors
are indicated by the red circle, warnings are yellow, and information blue.
Double click on the red error indicators, there may be a lot of them, but
read each one to locate those that may pertain, in particular, look for
Winlogon.exe and Csrss.exe errors..
I am assuming that you are able to start Windows with the shutdown and wait
2-3 minutes, rather than the restart, but if not, start in Safe Mode.
One note, for the GoBAck, I don't know if it is important or not, but the
recommended method was to first disable it by pressing the space bar during
bootup to access the GoBack options menu, then allowing the computer to
complete the bootup process, then remove it from add/remove.
So, it may be that it is still active in the boot sector. Do a search for
Goback, Roxio, to see if anything is found.
There are other possibilities, but, there really are many, so it may be a
time saver to perform a repair install.
It may be a third party software conflict..or a driver update..do you recall
installing any new software, or driver updates?