storage solution

Hi

I write from Spain, excuses for my english please

We need a massive storage solution starting around 2 TB and growing up. So
we need an scalable solution. It's not critical information so it's not
necessary 24h disponibility and no rapid access. It's bassically for storing
pdf, photos, and a little beat of backup. No security needed etc... It's a
files server.

I have found three solutions

HP 1 server + StorageWorks Modular Smart Array + 12 hdd's + installation and
3 years warranty it's around 12000 ? ( similar price for $ )
I just like this solution for the fiability of HP

ADAPTEC Array Altevo + 12MAXTOR 250gb+Fibre channel QLOGIC card ( 13400? ) I
just like this solution for the fibre channel the expandability ( another
jbod cabin is 4000? plus the hdd but we also need an aditional server

And my preferred solution is a SUpermicro server double Xeon with 15 250GB
maxtor hdd + installation and 3 year warranty for around 8000 ? it's more
adequate to our needs but limited wxpandability, no "modern" it's not a SAN
not a NAS it's just a files server and wich is the best OS that we can
use???

If anybody can give us it's opinion we will be very happy

Thanxs.