Windows Live OneCare backs up photos and pictures as part of the base product offering in the backup plan settings.
Go back to the backup tab, configure backup and click Change Settings in the lower left.
Select your PC and click.
Click Turn on backup
Select the change location link and select the drive you want to use for backup
Modify the schedule as desired for "When"
Select the file types as desired for "What"
Click next and save the revised plan with the new selection.
You can also optionally subscribe to online photo backup for an additional fee. You will see an option for this under the backup settings in OneCare.
-steve