One that has a working right click, left click, scroll wheel, and make sure it doesn't break when you spam the left key.
The "best" mouse is a subjective thing. Do some research and get what works best for you. I personally use a Logitech G502 because it fits my hand well, has adjustable DPI, and several buttons I can bind macros to.
You don't need a gaming mouse for minecraft. You aren't exactly playing a game that would mean the difference between life and death if you have on-the-fly DPI adjustments or if you are a few pixels away from a headshot. When you are fighting and using killaura there is little need for such precision gaming mice. The macros will be useful, but a number of hacked clients come with macros I believe. If anything, just get some hotkeys for your keyboard or something. I currently use the Roccat Kova+, but that's mainly because I play BF3.
I use the same style mouse as the one in the picture below. It does everything you would ever need a mouse to do and has never failed me.
Yep. I can't remember how many threads related to mice you've said the exact same thing with the exact same picture xD
I use the mouse that came with my laptop, nearly 6 years ago. I would never spend so much money on a gaming mouse. Would you?