I've inserted a hdd in an enclosure and want to format that drive, When I go threw the steps to format threw my computer where u click on the drive and the format drive (F in this case) i see capacity, file system (NTFS) and then allocation unit size (512 bytes, 1024, 2048 and 4096) how do I know which one to pick? then also volume label,,,?... and quick format and enable compression...?...
any help is appreciated....thanx

Leave the first and third to the default settings. With WinXP and similar your only option for file system will be NTFS if the partition is larger than 32GB. On drives under 32GB you would also have the option for FAT/FAT32 format, which is required if you will be accessing the drive from pre Win2K versions of Windows, DOS or a Mac.

The label is optional and can be changed at any time. It just helps you to distinguish one partition from another instead of remembering its drive letter.

what about the allocation size? how do i know which to pick, 512 bytes, 1024, 2048 or 4096?

Just use the default or the largest available. Choosing a smaller value just means slightly less wasted space at the expense of a small drop in performance. It's not critical - put it that way.