Creating one big continuous space from 4 disks

Solution 1:

If you convert the disk to Dynamic Disks (go to Disk Management in your System Management, right-click the disks and choose "Convert to Dynamic Disk"), you can then create a new "Spanned" volume. Windows will then join all of your disks together into one logical volume.

Note however that you get zero redundancy with this method of joining the disks, so if you lose one disk you lose the lot.

Solution 2:

What you can do is go to computer management then disk management.

Convert all of them to Dynamic disks and then you should be given the option to create a new Raid 0 / spanned disk that will achieve what you want.

I can't quickly find a picture for RAID 0, but after making the disks dynamic, the options should be in the right click context menu. After clicking on it, you should get to a screen similar to this:

That being said,I highly recommend against this unless you have a good backup plan. I personally have 4x 1TB drives and use them as 2x 2TB raid 1's (although recently been thinking about just using them as normal disks with rsync or similar between them).

And remember, even if you go for the above, always backup your important files.

Lastly, unless you have a Technet / MSDN subscription and a number of licences, Windows server 2008 can be expensive. Although I have a Technet, I use Freenas and CIFS. I am VERY happy with it.