Right click my computer on the desktop. A window opens (computer managment)
Left click on disk managment. (window changes to show hard drive)
Are there any partitions on the C: drive ?
There will be one for c: are there any others?
If so put in the Dell restore/recovery disk
Enter bios when computer restarts by hitting the del or F2 key.
in boot settings select boot from cd/dvd drive and restart.
Follow instructions