Turn on your computer and printer, and make sure they are connected.
Load your original document.
Click Start® Programs or All Programs® Dell Printers® Dell Photo AIO Printer 966.
For Windows Vista:
Click ® Programs.
Click Dell Printers.
Click Dell Photo AIO Printer 966.
Select Dell All-In-One Center.
The Dell All-In-One Center opens.
From the Send scanned image to: drop-down menu, select the program you want to use.
Click See More Scan Settings to customize your scan.
When you finish customizing your settings, click Scan Now.
To select where to save:
1. From the Send scanned image to: XXXXX XXXXX select your scan destination.
To further customize your scan job, click See More Scan Settings.
When did this problem started or this is the first time you trying to do this?? (Multiple image scan/Email)
As per the manual I didn't find any features like what you want.You can go through it I giving the link below for the Manual
DELL A920 Manual