i can't decide which one's the best.

I haven't yet played Tactics or New Vegas. Tactics because I've never prioritized it due to its liberties with canon, New Vegas because I lack the cash for the hardware and software involved.
Between those remaining, Fallout 1, 2 and 3, I can say I prefer Fallout 1 because I feel its atmosphere is consistent, its humor the right kind of dark, and the story is unmatched within its series.
I never expect to see another game make proper use of anaphase in a science fiction context.

I have this rant where I compare Fallout 1 to Parasite Eve. Remind me to rant it to you some time, if you don't mind never being able to look Parasite Eve in the eye again.

I've spent most of my Gaming time this year playing Fallout 1, 2, & New Vegas.

I loved all three, but for sheer scope I think NV may be my favorite. I got over 300 hours of playing time out of New Vegas with the DLC's and it really does a great job incorporating things from 1 & 2. Even Marcus from FO2 makes an appearance!

New Vegas' mechanics are completely different from the turn-based 1 & 2, but as someone who is really bad at FPS-style Games I had no problems adapting.

A real tough question. Every single one I've played has merit.

FO1 is probably the most complete perfect package.
Tight wonderful plot full of memorable events and stuff.
And it started everything..

FO2 is more of everything, done better and funnier. More freedom, more stuff to do.
The loss of cohesion is made up by everything being just so great.

FO:Tactics. The black sheep.
Ok, so the liberties taken with the canon boggle the mind! Granted.
So there's no roleplaying, just tactical combat. Not granted!
The story is on rails, but there is roleplaying and there are meaningful choices to be made here and there.
It's just the pointless fetch & carry fedex"quests" you don't get. The story is pretty good actually,
while the combat is the best of the series! Love switching to real-time for the easy encounters.

FO3 Much maligned, but it opened the wasteland, made it real. All about exploration and largely great.
What I didn't like, was the move to make the wasteland more politically correct, suitable for all audiences.

New Vegas A huge step in right direction. Everything's suddenly more adult and ambiguous. Loads of little nuggets for the old fans of the series, almost too much actually. Seems half the population had something to do with something in FO2.

I'll have to go with FO2 as the best one. If only by being able to do booze and drugs with Bishops wife and daughter and bed them both. Give me that in the next one!

New Vegas for me

I played F1 F2 F3 and FNV. I liked both F1 and F2....these are classics, even with the pixelated graphics. I love the fact that every time you kill someone with a laser mini gun, their torso rips into 2...LOL

F3 GOTY was nice for updated graphics and gameplay....but as soon as I picked up New Vegas....oh man, the nostalgia of F1 and F2 came into play really hard!

Played, in order: F2, F1, Tactics and playing F:NV right now. F2 remains the favourite and the only game that almost, almost had me gaming round the clock. I think I would have liked NV more if I started my experience from it and not Oblivion some months ago, because for me if you played one Bethesda sandbox, you played them all and after number of hours you sink into one, tedium creeps in and stays. That's why I skipped F3 - if I have to do the sandbox again, the least I can do is to pick up one with Obsidian's writing.

...on the other hand, maybe it's for the better I started with Oblivion - means I'm not picking up bloody every bit of junk any more. This game is horrible, horrible looter's hell.

i like all of them

I like Fallout 2 the best. Part of it is was Fallout 2 was the first RPG I ever played and second is I like the mix of humor and seriousness. I know a lot of people hate it but to me it makes it all the more special and unique. Fallout 1 may have beat the second since its more focused but the length of it just puts me off.

im kind of struck blind. I originally didnt like them much. I couldnt get into the 1st because of the time limit, fallout 2 is so far my favorite and is amazing. Fallout 3, eh not a fan. Ive heard great things from people who disliked 3, they said new vegas was good though.

What i really want, is any fallout game to be ported to a portable video game system. Thats all i ask, so that when the power goes out, im set. The video game companies should do this, they could make shitloads more money.

Edit-while i played fallout tactics in the past briefly, im much of a lone wanderer type so i have to finish fallout 2 before i attempt fallout tactics solo.

Fallout 2

I would say Fallout 1 beats Fallout 2 by a narrow margin. It's smaller, but it also makes more sense and isn't quite so silly. To be honest I find the incredible progress in the wasteland in the 80 years between 1 and 2 to be completely absurd. You go from Junktown and the Hub and the Boneyard, to Vault City and NCR and San Fran. It got far too clean, far too quickly. I want my wasteland DIRTY and RUSTED and BROKEN, damnit!

Both of the originals beat FO3/NV. While the exploration was neat, they didn't really have the replay value that the first ones did. Also FO3 took a step backwards in terms of progress. If it had taken place at the same time as FO1, it would have made sense. But a full hundred years later and the biggest settlement is Megaton? That's just absurd too. NV on the other hand went in the same direction as FO2, with EVEN MORE clean and sparkly and organized areas. The amount of rebuilding in the Mojave shows a deep-seated optimism that is COMPLETELY at odds with the Fallout universe, and even with the game itself.

Funny stuff was one of things I preferred about Fallout 2. I mean, the premise - Apocalypse as it could be in the sixties - is too goofy to be taken seriously anyway. So humour was mostly appropriately of gallows sort (my favourite!), popculture references were here and there but not in your face, and all that went really well with stuff like sledgehammering rats in the groin and planting dynamite on picpocketing kids.
Also, enjoying the hell out of "Old World Blues" right now. Obsidian still got it. :-)

One of these days I'll try Old World Blues,
got a bit fed up with FO:NV after doing Honest Hearts and Dead Money..
(purchased all 3 at the same time at some steam sale)

Fallout 2. Fallout 1 is enjoyable, but too short.

I've only played 1, 3, and New Vegas, and of those I'd have to go with Fallout 3. Those other games are both great, but they never create the same "holy balls" feeling I got from fighting a super mutant the size of a house, seeing Liberty Prime in action, slicing up housewives in VR, or any of the crazy set piece moments from that game.