Relax!
I've no idea why your software is locking everything up but your photos aren't 'on there' (as you put it).
All that the software does (in terms of finding your pictures) is to provide an 'indexing system'. Your pictures will be in one or more folders on your PC which will continue to exist even if there's a software problem.
If you're not sure where your photos are, go to Start > Search and run a search for *.jpg
That will find all pictures in the jpeg format (which is almost certainly what your pictures use) on your hard drive. Your pictures might be in the folder called 'My pictures' or your software might have put them into a special folder which it created. It doesn't matter where they are, as long as they still exist (and there's no reason why they shouldn't), they can still be accessed by
any suitable software.
You could try uninstalling Olympus Master and then reinstalling it but there's no particular reason why you need it anyway. The best image viewing software is IrfanView. It's free, it should be on everyone's PC and you can download it from here:
http://www.irfanview.com/
IrfanView can also be used for manipulating your images but, for greater flexibility, you might want to try Serif PhotoPlus 6. It's free and it's available (together with lots of other useful free software) here:
http://www.freeserifsoftware.com/