Regarding "default for opening all pictures"
You have not told us the file ext of your pics, .jpg, .bmp etc
Have you tried changing the default program for some types of pics?
open My Documents > explore, and navigate to your pictures
rightclick on one of the pics and choose 'Open With' and then select which program you want to view those types (.jpg for example)
If you want to view every picture with that ext with a particular program then tick the box at bottom for 'Always use this program for this type of file'
rightclick on one of the pics and choose 'Properties' and the 'General' tab to get to the same box to choose program to open picture.