If you have an Nvidia GPU then it is best to use SMAA. SMAA was developed specifically for Nvidia GPU's, similarly FSAA (Or SSAA) is developed for ATI GPU's.
TXAA is the most demanding type of AA, despite it being advertised as the opposite.
To be brutally honest though, you dont actuallt notice much difference betweewn any of them unoless you have side by side comparisons. You dont notice anything different in game.
Personally I just use 8xAA most of the time. Any more and it makes no difference to me. =)