|I have a recommendation for you with regard to a server.|
No matter what the server is going to be used for, no matter what hardware you buy, I highly recommend you buy something that is RAID capable.
It's always best to put your operating system on a RAID 1 and your data on a RAID 5 so ensure you buy something that has a controller that's capable of both.
I would also recommend that whatever you purchase has hot swappable drive bays and enough of them to allow for 2 drives for the RAID 1 and minimum 3 drive bays for the RAID 5. More would be preferable, but what I've just given you is what I consider the minimum.
If you don't know what RAID is, or what the different levels of RAID are (ie: 1, 5) then just google the term "RAID" and do some reading.