Cycling Shoes

[HQ6]

It was a toss up between putting this here, general discussion, and gear.

I have been riding mountain bikes recreationally for a few of years now. About two years ago I started taking indoor cycling/Spinning at my gym, got hooked, and started teaching about a month ago. For my birthday, my friends got me a gift card to the Bicycle Shop to get some shoes. Only problem is that I have no idea what I am looking for or at when it comes to cycling shoes. I have always worn hiking boots on the trails and my running shoes when I am teaching. So, if there are any cycling aficionados out there who could tell me what are the important elements one needs to look for in a shoe and if there is a preferred brand, I would appreciate any help.

OH and the shoes will be strictly for teaching the cycling class... at least until I get the whole unclip thing down cold. I don't want to bite it because I couldn't get my feet to the ground. Are you even supposed to wear the clips on trails?