  I don't understand most of what you wrote.  You need to enable UEFI (below), then convert to GPT before the installation of Windows.   The T610 supports UEFI, but you have to enable it.  Boot to the BIOS Setup (F2) and change the boot mode to UEFI instead of BIOS/legacy. Your alternative is to create a RAID 5 using all the disks but setting the size as something smaller than 2TB, then another RAID 5 with the remaining space.  Each array will show in Windows as a separate "disk" - you can then install normally to the smaller "disk".
Dear Sir, While I already configured RAID 5 with 5 disks, then on the step of installation OS (Window 2008 R2) I saw 2 separate partitions. and I can install on the partition that have 2TB only. Another one cannot. Thus while my OS installation completed, then I can use only 2TB, for another volume about 5TB is cannot do anything. Can I do RAID 5 with 5 disks (10TB)? I am awaiting your helpful for my posed. Thanks.  
Dell T610 with 5 Hard Disk (5x2TB) problem while create RAID 5 with all HDD. :(