My all-time favorite moment in my video game playing career is when i stepped out of vault 101 in FO3... the sun glaring in your eyes and the capital wasteland awaiting... awesome moment. I also never played any fallout games prior to this so i didnt expect any of it.

Liberty Prime assaulting the enclave positions was also pretty good

I'm with the OP on this. I spent ages on the lookout watching the sun set over the wasteland with the dust devils swirling in the streets.

Yeah, me too. I loved that first playthru when I saw the outside world for the first time. My jaw dropped open when I saw the size of the playground.

My other moment was sneaking into Old Olney and firing a missile launcher at 'you know what.' Watching the missile scream down the road in the vats camera gave my a huge smile on my face that stayed for hours.

I had a huge boner myself the first time I stepped out of 101.

I'm glad I was there to cherish that moment with you.

Liberty Prime getting blown to kingdom come was pretty satisfying.

Also meeting Eden was awesome for the first time.

Hmmm... When I left Vault 101 the first time it was a dark moonless night. It still was a wonderful sight.

Since the op said "all time favorite", mine would have to be walking out of Dagoth Ur and seeing the blue sky over Red Mountain for the first time in Morrowind.

still have mine, been awhile... getting kinda worried...

When Fallout 3 crashed, that was awesome.