Router Installation

Hi,

Im new to the industry but have all the book knowledge and no real practise. BSc, CCNA and now starting MCSA.

3 Locations, 3 Routers and a DIA to ISP via WiMax.

What protocol is best for the 3 locations at 2MB between each. Are the config files the usual and seen in most examples and books. Is the 1800 Cisco Series enough for 100 Users in 3 locations?

VoIP on any Cisco enabled switch possible with a VLAN running?

Just some guidance to past Forum Threads or Industry Standards would help.