You'll never open a JPG with Notepad, so wouldn't it be nice to get rid of that entry in Explorer's contextual Open With menu? Tech blog How-To Geek's step-by-step registry fix removes irrelevant programs from your 'Open With' menu by file type.
If you select the Open With menu and Windows Explorer pops up with a multitude of programs that have nothing to do with the current file type, implementing this solution will save you time and tidy up your menu. (Before you start getting regedit-happy though, it's always a good idea to make sure you backup your registry before going in to alter it.)
For a detailed primer on how to define which apps you want to show up in the Open With menu based on the file type you've right-clicked, head to the full post at How-To Geek.
Remove Programs from the Open With Menu in Explorer [How-To Geek]