Emulator Problem: Can't Save on Nestopia or Snes9x

I can't save or open "frozen" games on either my Nestopia or Snes9x. The Nestopia works just dandy until I click on my .frz file (which I saved to my desktop). Then I get the message, "Invalid file format: The selected file is in a format which Nestopia does not support at this time." I have a Mac. I downloaded Nestopia v1.4.1 from http://nestopia.sourceforge.net/.

My SNES9x has a similar problem. I can open and play the games just fine, but all my drop down menus are grayed out. If I go to the "option" tab, I cannot select "freeze state" or anything in that menu. I also can't even click "Quit" in the file menu so I have to force quit the emulator anytime I want to quit. I looked through its help section and it said I could save the games by pressing the number "1" and save the game in a menu filled with boxes. Well, that seems to save a file, but when I try to open it, I get the black screen that talks about the "bad checksum...." and then the screen goes black indefinitely.

Also, the first time I try to open a game it uses my HP printer's application. I need to specify that I want Snes9x to open the game. Don't know if that could be an indicator of anything.

If I save the game within the game like you normally would on the system, when I open the game up again later it isn't saved either.

I am really stumped and want to beat all my old, hard games!