How to use my external USB hard drive. Haven't backed up my C: drive for about 18 months on my

Question

Haven't backed up my C: drive for about 18 months on my Western Digital USB 2.0 160GB.
S/N: WCAL9671002
MDL: WD1600BDNN15

Now I've forgotten how to do it & can't find my little booklet.
When I turn the WD on the window that comes us says that the device has more than one type of content.
The choices are:
Play: Windows Media Player
Browse Media Files: Using Media Experience
Copy Disc: Sonic
Add Files: Sonic
Play: Music Match
Copy Pics to folder on Computer
View Slide Show
Print Pics
View this image in a slideshow
View pics on a removable media
Copy pics & view: Picasa
Download/View images
Play Video Files
Open Folder to view files
No Action

Don't see anywhere about backing up C:

I also pressed the button down from the power button (kind of looks like two pages overlapping). Nothing happened.
Seemed to me that was the button that I pressed to go to a choice of how to backup. But as I said, nothing happened.

Also pressed the third button - three leaf-like symbols
Nothing happened.
I can access the WD & see/access those files.

Any help would be most appreciated.

Thank you,

Sharon MacDonald
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