That power supply would work but I would personally spend a few more dollars and get an Antec EA 500 Green it has more power on the 12 volt for future upgrades and is a better all around power supply..
for the GTX 260
Recommended 42 Amps on the 12 volt rail for single card and 50 Amps for SLI. - is completely laughable. the list is pure crap for 12v amp recommendations. Even the manufacturers don't list amps that high and they over state everything.
(Minimum recommended power supply with +12 Volt current rating of 36 Amp Amps.)