double characters

I find that I frequently get double (or triple) characters when typing into the mailing list, or perhaps other aps. I forget what this is called--something about the repeat setup. Is it possible to slow this down, so as not to have the problem? I am using an IBM keyboard, same as the one on the Windows machine. (This is a noisy KB, but nothing types as well as these do! IBM made good stuff, way back when!) --doug