It's Free Linux server for me They can do everything an MS one can .
I also recommend linux for something like this. I decided last year that having a few more terrabytes of storage would change my life for the better. A discounted 'server-grade' HP box enhanced with some carefully chosen big disks came in really quite cheap, and no microsoft licences required. Getting windows (SMB) file-sharing to work was a challenge that kept me busy for a day or few, but it was all worth it in the end. If I ever get around to it I'll do more, like set it up as a web server or mail server, at no additional cost.
And, being linux, it's happy to sit on a shelf out of the way and operate in 'headless' mode (no monitor). Just telnet (or putty) in to maintain it, as long as you like (or would like to learn) traditional Unix-style command-line tools & text editors.