We're going with two web server as of this moment; one database server and one web/application server.

I'm wondering though, how bad is it for the web server to handle DNS, Mail, and Web Site Statistics as well as static and dynamic content all at the same time? Obviously the web server will function much better with less software installed. (More memory and CPU would be available for processing highly dynamic content.) Or might it be better to get a third server to handle DNS, Mail, and Web Site Statistics?

As a benchmark, estimated daily page views for all web sites should be around 100,000 initially and *hopefully* grow to around 500,000 a day. The web server is to be a Dual Xeon 2.0 with 2 Gigs of RAM. (Please - no wars about Xeon vs. Athlon vs. P4...)

Thanks for any advice in advance!