If all you have to solve for is 1 and 2 then I think your going about this the wrong way. You can do both with appliances - Firewall from Sonicwall or Barracud

If all you have to solve for is 1 and 2 then I think your going about this the wrong way. You can do both with appliances - Firewall from Sonicwall or Barracuda and you can buy any number of Raid x file servers. (i work for neither barracuda nor sonicwall, but use multiple products from both of them and for the money, their good) If you were going to build a full domain network with Active Directory, Print, File Shares, Exchange, etc... then I'd go with VM's We're (day job) a Dell shop and you can get really nice servers from them on the cheap. Get a few (2 or 3) big powerful servers, run ESXi on them, put the different systems in as VM's and your good to go. For VM's you want mammoth ram and processor. Storage is only important as how much you need to grow. Like you said, at that point, the OS and system are just a few files you can download and write to tape, transfer to a different server for DR, whatever. hell, if their small enough, you can burn them to blue ray. Its all about money and what you need to accomplish in a given amount of time. If money is no object, you can do whatever you want. If money and time are tight, your options will begin to get limited. I'm personally a big fan of appliances and use them whenever I can. Theres no Windows OS to patch, if i have a problem, i have 1 company to call, not 3 (server, os and software) and a lot of them can be bought with some sort of hardware assuance where they can replace the entire box within 48 hours if it fails.