in YOUR opinion

(i've beaten both)

personally i liked 2 better.

im thinking of replaying one of these:
arcanum
Fo1
Fo2
Planescape torment

pick 1 for me

play 2, and get this: http://www.nma-fallout.com/forum/viewtopic.php?t=56087&postdays=0&postorder=asc&start=0
remastered version made by hardcore fans (my uncle worked with the map design and a few other graphical things)
all the faq and stuff should be on the forum.

fo2 for sure man

play baldurs gate 2

this

but fo2 from your choices

Planescape Torment, one of the best games ever made.
The story behind that game is amazing. I loved the ending when he was finally mortal, grabbed the axe, and went out to battle.
The memory is fuzzy because it was so long ago. Plus it's based on AD&D 2nd edition rules, the most unforgiving and complicated rule set in the history of D&D.