My Macbook Is Damaged

Hey all.

My macbook has been damaged.my walpaper changed to blue and no dock,spaces.fortunately i know the shortcut to safari.do you know to repair my macbook.thx

Which Model of MacBook do you have?
Which version of OSX do your have?

Something to get started with:
1. Insert the OSX install disc
2. Restart your MacBook, hold down the C key until the Apple logo appears.
3. When the installer stops and you have a menu bar along the top of the screen, click on Utilities and select Disk Utility.
4. Click the First Aid tab.
5. Click the boot hard drive volume or partition.
6. Click Repair Disk.
7. Quit Disk Utility, quit the installer and reboot normally.