ZFS File Server - Purchase

Recently I purchased a Dell Poweredge 2950 server as a file server for my business. I compared prices from many sites online but ended up buying it from a local person on Craigslist. The company had gone out of business and was selling the server equipment that they had. The server specs are:

5100 Series Dual Core Processor 4GB of DDR2 Memory (8 x 512MB) 5x 1.5TB Drives

I decided that I would use FreeNAS and ZFS on this server.