Remote Offices Growing Fast – Servers

Hello. I have several remote offices that were at one time under 5 users. Now they are growing with over 10 – 15 users, and the once W2K Pro pseudo server can not accept more than 10 connections. I’m looking for the best solution, whether it be W2K Server or W2K Small Business Server, or Linux. My home office network has W2K Server / Exchange 2000 running, each remote office thru a VPN connection sends/receives email. It would be nice to be able to let each office handle email, interofficeemail would not route thru home office, and internet email would not route thru home office. Also, how well can W2K server Push/Pull company file shares, it’d be nice to have our files sync with other servers. Any Thoughts!! Thanks, Bill