These "hang" messages occur with many programs, and I believe even drivers,
not just Photoshop.
Like many things Microsoft they are not well documented and there are no
easy solutions. Try searching the Microsoft Knowlessthannothing Base and you
will see. Googling gets the same lack of answers.
I presume some running process is blocking a program from accessing the
memory it needs to operate but the potential causes for that are endless.
First see is you have a system restore point prior to when the problem
started and go back there to see if it solves the problem. Unfortunately
System Restore is a great idea but something of a crap shoot about whether
it will work or if there will be the system restore point you need when you
need it.
Right click on the photoshop executable and click on run as administrator
(in Vista)--east to try but not likely to work.
You can deactivate, uninstall, reboot and reinstall Photoshop but this often
does not solve the problem if it was not caused by corruption of your
Photoshop program files, which it probably was not.
Uninstall your current video drivers, reboot and reinstall the latest
updated drivers: it is astounding how many problems this cures in windows.
Turn of all un-necessary background programs, including antivirus programs
(unplug the network cable if you are paranoid) and see if that solves the
problem.
Scan for malware.
I presume you have contacted Adobe support: they are not as good as they
used to be, who is, but they probably don't have an answer for this one
anyway.