"Quick contacts widget" built into the phone (under motorolla widgets) works fine for this. If you have more than one action set for a contact (mobile phone, home, texting) then it will bring up a window to ask which one you want to use, but if you only have one option set up on a contact the window will come up the first time, and you can check a box that says "enable one touch dialing for this contact" which does exactly what you want. I decided two-touch dialing was good enough to avoid accidental calls, but if you like it it is available for you.