I am looking at some infinity 6.5" and the mounting depth is 2 1/4" deep this is fine, right? If not how big can I go? Also they are
"2 Infinity 6002I 6.5" 2-WAY 180W Pair Car Speakers"

Are these good speakers?

O yeah, it says cut out size is 5 what does this mean?

 

I bought some Infinity 6002si 6-1/2" Shallow 2-way Speakers off Crutchfield. I drive a 97 Civic. Not sure about the depth question, but mine fit alright, I had to make new holes for the screws though, but they did fit. Nice speakers too...

 

The infinity's should fit rather nicely. Hondas suck for speaker depth. But you should get the job done with no hassle. Try looking into neo magnet speakers for super low depth.