Virtual Disks Degraded (All)

Hi Dell Community Forum,

I have been stuck trying to fix my server for a few weeks. The situation is as follows:

1) Our current server is a Poweredge T310 with 2 hard disks X 2TB. The set up is RAID 5, with the PERC S300. The server OS is Windows Server 2008 R2 Enterprise. 

Recently I have been having problems restarting the computer, but on OMSA, startup, as well as storage manager, the physical disks are healthy. All three virtual disks are found to have been degraded on OMSA as well as during the boot-up.

2) After facing the problems in the last few weeks, I used Storage Manager to create a full back up, which is scheduled every 2 days (it takes about 1.5 days to create a full backup) on a 4TB external Hard Disk. This backup includes a Bare Metal Recovery

3) On OMSA, I am unable to simply rebuild the virtual disks. What should I do?

4) Would I be able to reformat the existing hard disks, and then recover from the last back up? Is there a risk that the back up image itself is corrupted? Would this resolve the issue?

5) Alternatively, do I have to buy new Hard Disks and attempt a recovery into new HDs? Would I be able to do this on the additional 2 slots that are currently not in use?

6) Is there a way to check the integrity of the backup on my external HD?

Thanks!