How To Backup NFS Underground 2 game saves

If you are a hardcore gamer then you must have played Need For Speed Underground 2. It takes days to finish the game. In such case imagine that your Operating System gives up or you had virus attack or a hardware failure. Your game play will go to waste. So you need to back your game save files. But where is it? NFS U2 stores save in C:\Documents and Settings\username\Application Data instead of installed directory.