Okay, here's the deal on the ECU.
Remove both battery terminals. Take this opportunity to clean the terminals and leads before the corrosion that is already there destroys them.
Flip on your headlights or anything electrical to make sure the car is drained of power.
Reconnect and fire her up. You don't need to wait a long time or anything like that.
Drive the car more aggressively for the next 100 miles or so. The ECU apparently relearns some parameters based on driving habits, so get it in while it's impressionable.