How to clean hard drive up dell latitude c640

[brownspook]

my hard drive showa that 16gb is been used but I have been through all my files and can only see about 3gb been used. where is the memory been used and can I clear it

 

[jsmakkar]

You said 3gb is used. Rest should be system / OS Files / applications / programs.

 

[brownspook]

thanks I am only running some basic programs - 3 players - windows xp and google chrome - where is the memory been used