reseting codes?

I just installed a remote starter on a Pontiac Transport 98. I am told that I might have generated a bunch of "error" codes since I initially didn't power all ignition wires and tested the remote starter in that configuration. How can I reset the car's computer in order to get rid of these codes once I complete my installation? Do I simply disconnect the negative battery terminal for 20 minutes or so? Before doing this should I note down anything ? in order to reprogram after reset? e.g., car radio anti-theft? (if I have one...) Thanks.

Does the check engine light or any other lights come on now when you start it by key? If not....nothing to worry about. If you have lights...pull the battery (-) for 20 minutes.

The van uses OBDII engine management.  If the Check/Service Engine light is on, it will go out on it's own after a number of drive cycles without detecting a problem.  Pulling the battery terminal off is not the answer, as this resets all monitors, not just the one you need to.  Sometimes as little as three cycles will do it.Keith