Next time try hitting Esc. Occasionally I have dialog windows that appear in weird places, including offscreen, where they obviously can't be clicked. Sometimes Esc quits you out of that dialog and you can do things again. It's worth a try anyway.
I had some problems like that after I installed a new drive and set it up as the main work drive for Photoshop. It gave me problems with Poser cloth nodes. I just had to get another drive, because the Cavalier Blue drive didn't write everything correctly. Some file types were corrupt like Windows prefetch for programs.
I don't know if this applies to you, but it sounds like the corrupt files. With that problem caused by a drive there is no fix for it, but replace the drive. From the sound of it Uninstalling Photoshop would not fix the problem unless you know how to delete everything Windows keeps after the program is uninstalled.
If it is a corrupt prefetch file all you need to do is delete it and lets Windows make a new one when you launch Photoshop again. It is easy to find, Just go to the Windows folder and look for a folder call Prefetch. In that folder you should see a file with Photoshop name.
If it is the hard drive this will not change a thing if the drive can't write that file correctly.
After it is deleted it is like starting Photoshop up for the first time.
MiraKialFeatured By OwnerNov 19, 2012Hobbyist Digital Artist
Try "switching the user" so you can go to the user select screen - don't log out, just switch user (that is, if you have Windows 7). Then go back into your profile. That might iron out whatever kookiness happened.