Need help setting a gaming server

Hello  
I want to build the most powerful server that can be built in one rackmount server chassis

Some of what i want:
->at least 4 CPU sockets supporting intel Xeon E7 the best one.
->Support for at least 4 PCI eXpress x16 i prefer version 3.0.
->support for PCI and smaller pci express.
->10GBE Networking.
->Usb and other essentilal connectivity.
->Support for tape drives ,optical drives ,floppy drives ,...etc.
->support for Raid arrays on all raid modes
->Support at least 16 hard drives
->Not sure about SAS and SATA !

-Which would be better SAS or SATA?!
-should i go for WD Enterprise class drives (SATA 64MB cache or SAS 32MB cache)?
-What should i do for cooling?
-Should i use Tape drives for backup or SAN NAS DAS ...etc?
-What is the best backup solution (live backup,scheduled backup,a combination of both)?
-Which is better incremental or differential backup?
-What is the best operating system for this setup regarding both security and performance(Windows server,linux server,FreeBSD server)?
-Which is the best Raid mode for both speed and protection (0+1,10,5,50,6,60)?
-should i use normal monitors on a desk or use the control thing thats composed of a keyboard and monitor mounted in a rack?
-to combine multiple servers with the same previous specs ,what is the best way to craete an efficient cluster server?

Waiting for the answer...  

Thanks