Changing the config register to 0x2142 will allow you to do password recovery and still keep your old config, although it will not be loaded into running. If you get the router up with the config register change and do a "copy start run" you'll be back to where you left off. Just don't do a "write mem" before this copy is done. Ensure you change your password to what you want it to be before getting out of enable mode, also admin up your interfaces.
Hope this helps,
Don
