How do I use dual user for Maplestory on a Vista labtop?

It needs to be a 64 bit version of Windows Vista for it to work for sure. If you have 64 bit, be sure to make both accounts admins. For the keyboard freezing, I would say dont switch users while maple is still up. Alt tab out of it and then switch. You might also be able to get the keyboard back by ending the explorer.exe process, but you would need to have takemanager open before switching.