I'm assuming you want to turn off all underlining in web pages you visit. The following explains how to do that:
1. Open up your favorite text editor. Notepad will do.
2. Copy the following line into a new file:
3. Save the file as:
to your *.slt directory located here:
This link will tell you where that directory is located for your OS:
Now, the next time that K-Meleon starts, this preference is copied over into your prefs.js file, which is located in the same directory. Technically, you could add that line to prefs.js but by locating it in user.js, you don't have to worry about it getting hosed if the prefs.js file is overwritten. If you have done this properly, links should not appear by default [CSS might override that in some cases - not sure].
Hope that helps!