We need to setup a new server, we want to setup a linux server. We are thinking about going with RHEL just because it is supported well. We then wanted to setup 2 virtual machines, one running Exchange, the other hosting files.

Can we use the regular RHEL workstation and buy Vmware? OR should be use XEN? What config would you recommend?

We are really new to this Linux Virtualization and linux in general. Mainly working with Windows and Mac servers. Please advise us.

Our system is a Xeon with 8GB of ram. Money is not really the concern we just need great uptime with very ease of use and configuration.

Thanks for the time

for great uptime you might want to consider a two-host scenario with a shared storage. and if money is no concern, and you're already looking at Red Hat, check out RHEV

http://www.redhat.com/virtualization/rhev/

Not sure it matters to you, but its likely that Exchange is only supported on Hyper-V and Vmware. I love VirtualBox, but we use Hyper-V at work and it works great for virtualizing Exchange (among other things)