Fallout

FO3: Guns. Long-medium range guns. Real time combat plays like trash so max out your Agility and get used to living in VATS. Melee builds are also an option

FO4: Maximize your scrounging and take every buff that increases the amount of something you find. You're gonna need a lot of simple resources for base building, and you'll not lose stock of essentials like caps or bullets. Dealer's choice how you actually play the game, but real time aiming and shooting actually work in this one so VATS isn't essential the way it is in the other games

FNV: Weapons don't matter as much, but pick a weapons stat and live by it. Make sure Speech is one of your top skills also. Once you get to the strip you can do a lot with a speech check.

Getting 100% achievements in New Vegas meant playing every weapon build, and of all of them, Ninja was the most fun.

Just sneaking around and VATSing enemies with the deadliest melee weapon you can find was a blast!

Here's my idea of a very optimized Fallout 1 build for a vanilla kind of playthrough.

An exotic alternative would be a high luck build that pumps all the skill points into gambling until you can consistently come out ahead at casinos. Then you go into a casino, hit the enter key to gamble until you have a ton of caps, then go and buy all the best gear possible and absolutely stomp the early and mid-game quests. Very fun to do with an energy weapon combat build.

If you are looking for fun maximized runs I'd try a few of the novelty runs. For example getting the cannibal perk as fast as you can and going for the Meat of the Champions awarded perk or an unarmed power armor build in Fallout 4.

If you are playing on PC with mods you can create a lot of goofy fun playthroughs. Like the Any Mod Any Weapon mod and really focusing in on creating outrageous overpowered weapons.

I feel like some of this isn't the best for new players though. To get the full raider experience in Fallout 4 for example I feel like you need to do a fair amount of strategising and make some decisions that might not seem straightforward.

To be honest with you I've found stealth, lockpicking, science, and repair to be some of the most important stats. In fact if you have the Operation Anchorage dlc for Fallout 3 you can gain access to one of the most overpowered armor sets in the game. A Chinese stealth armor suit that acts like a stealthboy when you're sneaking. And with all the sneak attack critical perks you can get it turns into a skyrim stealth archer thing.

I basically try my best to make my character a master of all trades so I can get every secret unique item in each game. That and being able to kill an entire room of people with one plasma rifle shot each is very satisfying V.A.T.S. or otherwise.

Fallout 4 is a little harder to fully max your character on so I use stealth more than anything when it comes to combat.

You haven't lived until you have done an explosives build in New Vegas.