Hi everyone! I'm new to this website and new to Ubuntu. Thanks for being here!

I need to setup a file storage server. People will be writing to and from the drive all day with average reads / writes of about 100mb. Regular reads and writes of ~2 GB once or twice an hour. About 15 people will be accessing it for two different drives. So I'm having a hard time figuring if I should build or buy two ~$400 machines or one <$800 machine.

The problems I'm facing in addressing these issues are my lack of knowledge and a budget. Common problems I think.

I see the top options as:
Machine I will build
Ubuntu Server 64bit
Win Home Server 2011

Specs of the machine would be:
4.1Ghz Quad Core FM2 AMD CPU-GPU-APU
16~32GB RAM
Small SSD around 64GB for OS
2x 2tb mirrored
2x 2tb mirrored

Prebuilt NAS
QNAP NAS (link to prospective hardware)
Preinstalled no more than 1GB RAM

What do you think the best choice is?

Please consider I only have 2 weeks to implement a solution for our storage needs. I've only ever tinkered in Linux GUIs of varying distros, but I bought a book on PHP and learned it pretty well within about 3 months. My gut is with Ubuntu because it seems well supported and highly configurable, but I'm worried I wont be able to learn it in time. It seems like it it's going to be tricky right from the get-go (installing it due to UEFI), then setting up two RAID 1's. I'm worried I may need to use Windows Home Server 2011, just because the interface may be more familiar to me, but then maybe it only allows 10 users or some other poor restriction. Notification of drive failure is also a must-have which is really the primary reason I even consider QNAP (little green lights).

I hope you can imagine, but not feel my stress of needing to get this done within two weeks. I'm currently reading a book on patience, ironically (or by a gift of God).