Assuming you are doing a forced-shutdown or power interruption to get out of that windows screen it should bring up “windows was shut down unexpectedly” and three options during the reboot cycle. Choose SAFE MODE. If that allows you past the point where it was hanging up there are several things you should do. First do a full backup of all your files. Then you can start working on diagnosing the problem. Definitely check out the PROGRAMS section and uninstall anything that was installed around the time your problems began, and anything you don’t recognize that was installed recently.
How do you do a backup in safe mode? I’ve got a similar problem.