Photoshop and Illustrator are design industry standard now. AfterEffects and inDesign would be solid assets as well. Both CC and CS6 are ok. I wouldnt recommend cs5 just because cs6 is a huge leap forward in terms of pixel perfect design and pretty much everything else.
So if you plan to ever start working in a big company i suggest you learn those, you are expected to work with sources from those programs. CC made "buying" those way easier so i d expect to get a full CC sub, everything else could be a pain to get considering software costs.
As for slicing — there are plenty of tools to do it in cs6. PNG Express would be a good thing to start with.
Get familiar with layer comps in PS and art boards in IL and you are good to go.