I know. the South Park fanboy cringes at what I had to do, but step two was the mystery in this instance lol

1st time safe the town.
2nd time blow it.
3rd time safe it again.

If i play 4th i maybe kill all citizen in town and turn it to be "My town". :D
(I heard you can't kill kids ,but i never try before so i don't know about it.)

yeah its true. I tried to kill those snotty brats in Little Lamplight but couldn't draw a weapon there

Well I was a good boy and I disarmed the bomb, I really couldn't find a reason to blow it up. Maybe I'll do it on my next run just to see what it looks like, then I'll get the penthouse in Tinpenny Towers.

blowing up megaton is prettier in the night time.

i was a savior for megaton but the villagers got in my nerves, so i said, "fu#$ it your all dead tonight!!"

but before that i just had to kill the owner of saloon by slitting his throat in his sleep. i worked hard earning 100 caps for mayarty regarding the main quest, but nooo now saloon owner asking for 200 caps!! DIE!!

Is it possible to play through Fallout 3 without being given the option to blow up or save the town? I exited the Vault and didn't see Megaton anywhere.

A big BOOM!!! @ night. Nice

Your two sentences don't seem to match up, but I'll answer everything and you can piece it together.

1. If you know in advance who the choices come from, you can avoid both conversations and offers to disarm and blow up the bomb. So yes you can never have the option technically, but 99% of everyone will accidently walk in on those conversations their first time through.

2. If by the second sentence you really meant with the first sentence is "Is it possible to play through Fallout 3 without going to Megaton?" the answer is no. There are story related elements there. If you really just want to know where it is, just head in the general direction to your left. I went through the school first to get there, but you can get there without going through the school first. I don't suggest it though. There are lots of goodies and some good beginner's training fighting raiders in there.

I probably meant this second one.  When I heard about the choice being offered, I had assumed that I would be immediately thrust into the question, and couldn't avoid it.   Well, when I left the Vault, I walk straight, saw a town name "Spring" something I believe, and then wondered where Megaton was.  Well, it was so bad for me, I forgot it was even called "Megaton".  it was just barren.  So, the question popped into my head: Is it possible to play the game without ever having to deal with Megaton?

I saved Megaton and then I loaded a save and blew it to pieces!!