PSE 4.0 crashing when saving/working with file

[mikora7]

I'm hoping someone can help me. I have been having the same issue over and over. I open a file, copy the element, paste it onto the page I'm working on and resize. Then either it crashes there or when I tell it to save the changes, it crashes then. I'm so frustrated! It won't let me work with anything that is bigger than 2-3" in size w/out crashing. Can someone offer advice on what to trash or re-install, whatever needs to be done to correct this problem? I'm using 10.4.11 on an intel core dual processor. For what it's worth, my Airport Extreme went down recently and I've been messing with getting that back up and running and possibly I caused a conflict there? (I still don't have my wireless back up...)