To your first question I can only think that perhaps the person sending you the pic is on a different network and that's the only way you can view pics from them? I get pics sent to me in a text message but that's coming from someone who is also on my same network. You should call your provider on that.
As for the notification reminder. I believe there is a way you can have it notify you of a missed call/etc. once but not continuously. The blinking red LED is used for that. However, on Handango.com - there is a program called Missed Call Notifier that you can buy that might have that function.