Actually the 2500K has a better price/perf ratio. At stock clocks the 2600K is about 25% faster than the 2500K, but only in well-threaded applications such as video encoding. The problem is that it costs about 43% more, so it's a waste of money if you aren't planning to use it in multi-threaded applications.
And if you don't plan to overclock, even the 2500K is more than you need. You could go with an i5 2400 instead. None of the uses you listed are particularly CPU intensive.
Notice I said quality, not quantity. Many people come here asking for help when their computers are having boot problems and/or random freezing. The culprit often turns out to be a cheap, unreliable PSU. If you stick with brands like Seasonic, Corsair, and Antec, then you'll be far less likely to have problems. The reason why I brought this up is because it is one of the things you could use the extra money for by going with a cheaper CPU.
Concerning the chipset: Since you don't plan to overclock, and the SSD you chose is big enough to use as a system drive (no need for SSD caching), then you're probably better off with H67 instead of P67/Z68. Beyond that, it's down to choosing a reliable brand (i.e. Asus, Gigabyte, Intel, ASrock) and narrowing it down based on the features/layout you want.