In Apple Configurator, Mac OS X Server, or even the poorly named iPhone Configuration Utility, you can create configuration profiles. In these profiles, you can set up all of your wireless networks and even some restrictions and other miscellany.
Once you’ve created the profile, you can load it on to the device through Apple Configurator or by downloading it from the web or through email. You’ll need to confirm a few things and it will be loaded in and the settings will be applied. The chicken and the egg with the wireless settings is that if you plan to use the web or email, they need to be online first. That said, you can push out the profiles through the Configurator.
To answer your second question: the only time that you lose access to the camera roll and whatnot is when you flip on supervision. If you choose not to supervise the devices in Apple Configurator, then it’s business as usual.
Dropbox recently added to feature to pull of photos and videos off your iOS device every time it connects. This may be a good option for you because it will allow your to keep a shared folder full of media.