Of couse Fallout 1, 2nd fallout long and boring except for Klamath, Den and Reno. Fallout 1 shows everything, I played Fallout 1 very long time ago, but week ago I replayed it again and Fallout 2. I bored at F2 on 2nd playing hour, and don't think I'll play it again. Fallout 2 is good, but only because it's continuation of Fallout 1 (don't take in account that it's more newer Fallout so it has more items/perks/comfortable to play). Fallout 2 is only you completed Fallout 1, killed overseer in the end watched movie how your character goes in the desert, and... end. And you want to continue playing. Fallout 2 itself without 1st not a game. Also replaying Fallout 1 showed me true BoS... because I barely can remember anything when I was 10 years old when I last time played Fallout 1.
Fallout Tactics and Fallout 3 totally other story and has almost nothing with orginal Fallout. Fallout Tactics is interesting to play alone for sniper using sneak and real time only, while Fallout 3... I think Oblivion much more better than Fallout 3, they shouldn't have done this.