"I think" the super duper mart quest. It's nothing like your ordinary first quest in video games, it's not some tutorial to get you used to combat or something. (though your "first quest" is also a choice. but most people did this early on) You're looking for food to scavenge for the quest so the quest giver can write about it in the "wasteland survival guide" and once you enter the super duper mart, you notice that it has 5-6 raiders in it, and you get no "Listen champ, what you need to do is.." radio pvssyr, you're on your own. personally I grabbed the food right away without being seen (sneak character) and then you get the Optional quest tag and you can also find medical supplies to report to the quest giver about, however that is on the other side of the store (unknown at the time) and through the raiders. A short while later (robot jumps out of a cake...figuratively speaking of course ) and you exit the store, then "sometimes" a boy will approach you can ask for help with his town, leading to a whole new adventure, often times you'll have a Ton of stuff to do because getting side-tracked is easy, but unlike most games, getting side-tracked in Fallout isn't a bad thing! it's one of the BEST things.