I am looking at a set of KNS Gen ST AR-15 Non-Rotating Trigger/Hammer Pin (link Provided) and when it comes to the trigger/hammer pin it has options. Can someone tell me what the difference are and what I might have to get.

Gen ST Build-A-Kit

The differences in the options??

Well most triggers don't need them at all.  Some do, but those are mainly cassette type triggers (but not all cassette triggers: ie. Wilson Combat TU series).  the other options come into play only if you have a non-standard pins.  Measure your current pins and then you'll know if yours is standard or not.  

You other options are colors:  Pink is a nice color in a non-threating sort of way. It just screams diversity, and generates that kumbaya happy feeling........

Well for me it will be red, I have built a Left Hand AR with a Rainier Arms Low, Stag Left Upper, Aero Fluted barrel, with a bunch of parts from Strike Industries Red Line series. They just don't offer the pins in red so I have to go some where else and I like the looks of these. I just wanted to make sure I was getting the right thing.