5 People?
Mac Mini for file server.
Mac Mini for backup server. Don't even think of using FileVault for your encryption.
Mac Pro for content creation. Get high GHz instead of cores as you were not specific on the actual apps you are using. If it is going to do everything, get the 6-core.
You don't need the Pros for your limited serving needs.
And if you need them for i/o get the slowest. You do not need any major processing. Now you Go!
Mac Mini for file server.
Mac Mini for backup server. Don't even think of using FileVault for your encryption.
Mac Pro for content creation. Get high GHz instead of cores as you were not specific on the actual apps you are using. If it is going to do everything, get the 6-core.
You don't need the Pros for your limited serving needs.
And if you need them for i/o get the slowest. You do not need any major processing. Now you Go!