Disk Management in win2008
Disk Management is a system utility for managing hard disks and the volumes or partitions that they contain. With Disk Management, you can initialize disks, create volumes, and format volumes with the FAT, FAT32, or NTFS file systems. Disk Management enables you to perform most disk-related tasks without restarting the system or interrupting users. Most configuration changes take effect immediately.
Added new features
Simpler partition creation. When you right-click a volume, you can choose whether to create a basic, spanned, or striped partition directly from the menu.
Disk conversion options. When you add more than four partitions to a basic disk, you are prompted to convert the disk to dynamic or to the GUID partition table (GPT) partition style.
Extend and shrink partitions. You can extend and shrink partitions directly from the Windows interface.
Initialize New Disks
In Disk Management, right-click the disk you want to initialize, and then click Initialize Disk.
In the Initialize Disk dialog box, select the disk(s) to initialize. You can select whether to use the master boot record (MBR) or GUID partition table (GPT) partition style.
Change a Master Boot Record Disk into a GUID Partition Table Disk
Master boot record (MBR) disks use the standard BIOS partition table. GUID partition table (GPT) disks use unified extensible firmware interface (UEFI). One advantage of GPT disks is that you can have more than four partitions on each disk. GPT is also required for disks larger than 2 terabytes.
You can change a disk from MBR to GPT partition style as long as the disk does not contain any partitions or volumes.
You cannot use the GPT partition style on removable media, or on cluster disks that are connected to shared SCSI or Fibre Channel buses that are used by the Cluster service.
Back up or move the data on the basic master boot record (MBR) disk you want to convert into a GUID partition table (GPT) disk.
If the disk contains any partitions or volumes, right-click any volumes on the disk and then click Delete Partition or Delete Volume.
Right-click the MBR disk that you want to change into a GPT disk, and then click Convert to GPT Disk.
Reactivating a missing or offline dynamic disk
In Disk Management, right-click the disk marked Missing or Offline.
Click Reactivate Disk. The disk should be marked Online after the disk is reactivated.
Changing a basic disk into a dynamic disk
In Disk Management, right-click the basic disk you want to convert.
Click Convert to Dynamic Disk and follow instructions.
Changing a dynamic disk back to a basic disk
Back up all volumes on the disk you want to convert from dynamic to basic.
In Disk Management, right-click each volume on the dynamic disk you want to convert to a basic disk, and then click Delete Volume for each volume on the disk.
When all volumes on the disk have been deleted, right-click the disk, and then click Convert to Basic Disk.
Change a GUID Partition Table Disk into a Master Boot Record Disk
Back up or move all volumes on the basic GUID partition table (GPT) disk you want to convert into a master boot record (MBR) disk.
If the disk contains any partitions or volumes, right-click any volumes on the disk and then click Delete Volume.
Right-click the GPT disk that you want to change into an MBR disk, and then click Convert to MBR disk.
Here found some refference document
How to Expand and shrink tasks with Windows Server 2008
Adding a New Disk to an Existing Windows 2008 Cluster