Advice needed from those in the know!

There are plans here to run a wireless network from a college and provide an internet connection to 15 learning centres.

I have been sent information for me to select a broadband provider for the college but I have no experience of what I actually need.

1) Is there any advantage to static over dynamic IP addressing?

2) Number of IPs... What is the difference between having one or multiple

3) Do I need PAT and NAT?

4) What would be an ideal connection speed? I think the 1MB package would be insufficient.

Cheers guys for keeping me from looking incompetent!