Oh yes, KM is slightly old-fashioned, and those accel presets probably date back to the first time this function was added... Just a hint, nearly all of the wiki is more or less outdated, most parts are ages old. Only the download page, news, a few chapters of the faq and an odd bit here and there still get occasionally updated. But one can always ask in the forum.
Glad you found what you needed, although not the slightest idea what you meant really, like the rest of us here ;-)
At the moment my best guess would be, perhaps you wanted to know where the settings can be found...? If yes, that mouse accels menu is just one of several possibilities. There are more ways in the menu Edit/Configuration, allowing to tweak every single button and shortcut and menu line. Although that requires manual editing, so is more work. Or perhaps you wanted a little popup menu offering each time the various opening choices?? But then again, that's already there at a simple right-click.
General tip: There are lots of right-click options in KM, also on some buttons, what most people overlook because they expect a little arrow for that. It's not there in KM to save space. So when searching for a function, I'd first try right-clicking everywhere, on buttons, tabs, links, images, selected text, etc.
SeaMonkey uses aprox 40 MB of ram more then KM, not to mention web-navigation is a lot slower then K-Meleon.
Oh I didn't actually mean to use it as browser, just to set the same shortcut settings, as seen in the table column.