Here is a simple method to hide ur disk drive
>>open control panel
>>go to administrative tools
>>click computer managment
>>now a window will appear
>>click disk managment on the left column now u will see all disk drives >.suppose u have to hide local disk E
>>right click on local disk E and choose "change drive letter and paths" now a small window will appear showing ur letter"E" click remove and then ok..... open my computer u will not see local disk E to bring back repeat the abv steps but when u open disk managment the drive that is hidden will b without any letter.
>>right click on it and
>>choose "change drive letter and paths"
>>press Add and than Ok.