Shutterfly
Although i don't have a tonne of experience, this service seemed to be really easy to use. You will need to sign in, but once you are a member (free) you can look at albums, buy prints, post pictures and much more.

Snapfish
I think you need to become a member here as well, but if you are familiar with this service and like it better please email us and we will share our album with you (you can also buy prints and stuff here)