You can specify which programs it should use when you issue these types of commands, by going to Options: Preferences and looking for the Applications. The Applications dialog box lets you browse through your computer and assign which program should be used when you make this kind of request. For example, when you choose View: Source you might want Netscape to open a copy of your file in the simple Windows text editor Notepad, or the Macintosh text editor, SimpleText. Using the browse button, find the program and click on it to select it.
If your computer has lots of memory you may even prefer to have Netscape open your favorite word processor when you choose View: Source. The choice is yours!