So right now I am riding my fixie for the time being...I like it, but with the NYC winter coming up I am looking to get my commuter prepared.

I was given this Canyon Land Full Force (not my picture)


However, I would really like to make it into a better commuter bike (I really do like the bike below's setup with the bars and fenders)


My question is:
- The bike is a grip shift setup - can I convert that to other shifters (brake lever shifters) if I was to also change the bars?
- How hard do you think it would be to modify the bike?
- Right now I believe the bike has 26"s on it, for NYC roads what do you recommend (considering the snow).
- I wanted to run these fenders on it (http://ecom1.planetbike.com/7056_5.html What should I be looking for for mounting points on the bike to know if I can or not?

Appreciate all the feedback, I am still new to this commuting thing so I am not looking to spend an ample amount of money in the beginning. Believe I can make due with what I am at the moment.