new servers spec?

[MrPstv]

We are looking to purchase some new servers, what would be an ideal spec for running a CMIS server and a curriculum server .what would it cost to migrate and purchase? we currently have a 2.8ghz intel dual xeon with 4gb ram for curriculum and 3.06ghz dual xeon 2.0 gb ram for admin these would be setup as print and wsus servers(would you replace these?). We will be adding a further 80 netbooks to 100 varied machines and laptops. Would you replace Admin office machines with workstations instead of a standard run of the mill pc that would be used for curriculum based software?

Help on this much appreciated please.