In the script editor there's an entry "Scene_Title." I haven't done much work with RGSS aside from breaking things, but I'd bet the coordinates for the menu are in there (lines 42 & 43 look promising). You should backup your entire project folder before you mess with it though.
Also, I believe title screens are 640 x 480, so I think the feet are going to get cut off.
This is shaping up. Before it was "nice" and "serving its purpose". Great Job!