JDM von Weinberg , Jul 03, 2013; 09:00 p.m.
PS CS6 would last you and you would never grow out of it. I think it is good enough to stay with even if Adobe goes starkers and does this monthly license thingie they are talking about for after CS6.
Lightroom is much cheaper, does enough for many people. It has had many Photoshop-like image editing features added to what was originally an image management program.
For the needs you have right now, something like Lightroom should do, I would think. I personally use Photoshop, but many people here tell me, repeatedly, that Lightroom is all one needs.