After many trials and errors these are the settings I used to get video and snapshot email working on my DCS-942l with NC RoadRunner:
Recipient E-mail Address: XXXXXX@nc.rr.com
SMTP E-mail Server : mobile-smtp.roadrunner.com
Port (range 1 to 65535): 587
User Name : XXXXXX@nc.rr.com
Password : XXXXXXXXXX
Sender E-mail Address : XXXXXXX@nc.rr.com
Hope this helps!!