My aperture library is located on my time capsule. Maybe this is the problem?
That will be the problem.
The Aperure library needs to be on a drive formatted as Mac OS X extended, and Apple advises against storing the Aperture library on a network volume.
I'd move the library to a directly connected drive.
In any case, run the Aperture Library First Aid Tools to repair it. That is highly recommended after force quitting Aperture:
Also what are my options for when my hard drive quickly fills up?
You could relocate some of your referenced originals to an external drive - for example the originals for older projects that no longer need editing. Then you can save space and still work on the newer projects, even if the external is not connected.
I wonder why aperture has been running fine for over 18months until now?
If a transmission error corrupted the library that may occur randomly.
But the same symptoms can be caused by importing images or videos that cannot be processed. Can you start Aperture, if you launch it with the Shift key held down, while clicking the Aperture icon? That will defer the generation of previews.
If Aperture does not hang in this mode, it usually means, that you imported someting that Aperture cannot process.
I have only ever imported images from the same camera in the same format so I'm sure the problem is purely what you said about the time capsule. I have a library located on my HD for when I go away on trips and when I change to this library aperture runs smooth.
I am now merging both libraries which will take up about 80% of my 500gig HD. I just wonder if there is another way to have what I used to have so that I can access all my photos at any time through aperture. Maybe light room is set up differantly?