replacing battiery

Hi ya'll, got a question, what is the proper way to replace a battery in a vehicle, I recently swapped the battery in my 2000 Tahoe with the battery in my wifes 03 Envoy, same rattings on the chart at Wal-Mart where the battery came from. After I swapped it out, the Tahoe would start and then die, I could start it and rev it up, take foot off gas, it dies. My dad asked how did I take the cables off, I took off the hot side then the ground side, he told me to take off the hot and put it back on, and sure enough it fixed the problem, is there a certin way to do this, I have always taken the ground off first, so as not to short the hot term to the frame or inner fender. So is the proper way to D/C the ground, then the hot, and hook the hot back up first then the ground??? Any ideas what happend??? Thanks