Oldsmobile/Buick Repair: my car wont start, jumper cables, buick regal

Question
I have a 99 Buick Regal v6 with 105,000 miles.  I came out of a store yesterday to find that it would not start.  Someone gave me a jump, but I don't think thats what made my car start.  I drove home shut it off, and attempted to start it again, and nothing.  I tried later and she fired right up.  I drove to work, and it sat for about 6 hours.  When I got off work it started right up.  When i got home i turned it off and it started three times no prob.  It started this morning three times, and then the service engine soon light came on and wouldn't start.
Any help would be greatly appreciated.
Thank you!!!

Answer
Amanda,
  Would not start, does this mean the engine starter would make a cranking noise and the engine would spin over and not fire up or does it mean when you turned the key to start nothing happen/no noise?
  If someone used jumper cables I would lean to you meant nothing happened/ no noise when trying to start. If so do you have a little black thing embedded in the ignition key? If so that system may be faulty. Its called Pass-key and its an anti-theft system. Normally the key is fine but the ignition switch is skewed. You would need a ignition switch and a new matching key with the same value in the above mentioned "little black thing" (a resistor assigned to your anti-theft controller). If you don't have a little black thing in the key and the engine still didn't make noise when you cranked the engine but did later on it own without another jump you might have a corroded connection on the battery at the cables. Some times it in side and hard to see. If the engine did make noise and cranked but didn't start the list gets bigger. The big key is the check engine light and since its a 99 you need a special code reader the system is an "O.B.D-2" system, meaning on board diagnostic # 2 and it cant  be looked at with out a special scanner/code reader. Let me know just what happen as I asked above about the crank or no cranking.