Difference between Dell Backup and Recovery Manager and Windows Backup and Restore

Hi! I just bought a new Dell Vostro laptop and I am trying to figure out how to do backups.

What is the difference is between making a "system backup" in the Dell Backup and Recovery Manager (DBRM version 1.3) and a "system image" in Windows Backup and Restore? (I'm using Windows 7.) Do I need to do both to be fully backed up, or just one of them? It seems to me that they both do almost the same thing. Which one is the best method?

Thank you very much in advance!