Modifying the Autocheck Time-out Value (Windows NT/2000/XP)
When Windows is not shutdown correctly it will perform an AutoCheck using CHKDSK on the next restart. This setting controls the time delay before running Autochk or whether it is run at all.

Optimize the Contiguous File Allocation Size (Windows 95/98/Me) Popular
This setting optimizes the file system by specifying the minimum amount of free contiguous space needed before writing a file. Larger values are especially useful for disk intensive applications to reduce fragmentation.

Disk Defragmenter Options (Windows 95/98/Me)
These settings allow you to control the default options for the disk defragmenter (DEFRAG) utility.

Automatic Boot Disk Optimization (Windows XP)
Windows XP includes a new feature that will automatically optimize the the disks on boot if required. This setting controls whether this feature is enabled.

Disable Screen Saver When Disk Defragmenter Active (Windows 95/98/Me)
If the screen saver becomes active while using the disk defragmenter it can slow and interrupt the process. This tweak disables the screen saver when defrag is being used.

Disable Low Disk Space Notification (Windows XP)
This setting controls whether you receive a "Low Disk Space" warning when free disk space reaches less than 200 megabytes.

Disable ScanDisk After Improper Shutdown (Windows Me)
Normally if a system is shutdown improperly scandisk will run on the next reboot to ensure the contents of the hard disk are valid. This setting stops scandisk from running automatically when restarting.

Control How NTFS Reserves Space for its Master File Table (Windows NT/2000/XP)
The NTFS file system contains at its core a file called the master file table (MFT). For every file on an NTFS volume there is at least one entry in the MFT. This setting controls the amount of space reserved for the MFT so that it does not become fragmented and slow system performance.