BleepingComputer.com: Problem with Gimp

Here's how the problem started. I took some pictures with my Wifes camera ( 12.1 mp ). I've done this many times before with no problems. So... the first thing I do is connect the camera to my computer and open the pictures with Gimp - where I scale them from 4000X... to 500x and save them in my pictures folder, so they are a reasonable size to send in emails. But now, any picture I open in my pictures folder opens with Gimp by default - not just the recent ones.

When I right click on a picture, 'open with Gimp' is the first entry in the drop down menu - so I guess it has somehow been set as default. I can't figure out how to undo that which has been done. I thought about uninstalling/reinstalling Gimp, but I'm thinking that the a setting in my pictures folder is the real problem. I'm lost right now, so any ideas?

Open Nautilus, go to where one of the files is, right-click it, choose Properties, click on Open With, and choose a different default.

You can also go through ~/.local/share/mime (a directory of files) to see which one in there handled the filetype, then change or delete it. Just be careful with the syntax if you alter one. It's plain text xml, but you need to make sure all opening/closing statements are done properly. You could also move it temporarily to your home directory to test things before committing to deletion. (Either action may require a logout/in to take effect.)

Thanks for the information stiltskin, all is back to normal now - pictures opening with image viewer. I used the GUI route you mentioned to correct it.