I have to disagree about 800 speed film not being the kind you find in disposable cameras and at discount stores!
I had a TERRIBLE time finding disposable cameras loaded with anything OTHER than 800! Kodak, Fuji, they are all 800 speed. The cameras at Sam's and at Target are almost ALL 800 speed. Even the plastic SpongeBob print camera I saw had 800 speed film in it. The two disposables my son got for Christmas from friends (intended for him to use on the trip) are 800. We are leaving those at home because I don't want to deal with it!
I have 5 disposable loaded with 400, and 7 rolls of 400 film for the camera. I love disposable cameras, but you really have to be careful about what film they are loaded with.