I'm looking into buying what is described as a 'compact system camera' which is like a point and shoot, only a little larger. This will be my first experience with cameras of any variety, so I know next to nothing. Do these cameras take only rechargeable batteries? I read that it can take up to 5 hours to fully charge a particular model using the USB connector. Do most current models suffer from this limitation, or are there ways to speed the charging process? Can the camera be operated while it is charging, such as transferring pictures over its WiFi connection, or does it need to be completely off?
A CSC, or (more commonly) mirrorless camera is actually quite a bit NOT "like a point and shoot, only larger." You really want to do a bit more research, as these cameras are significantly more expensive to own than a fixed-lens compact because of the interchangeable lens mount, which means that the "camera" (body) is really only half the camera. The other half are your lenses, and they can be significantly more expensive than the camera itself.
Most of these cameras only take rechargeable proprietary battery packs. How long it takes to recharge varies, but it will typically be measured in hours. Most shooters get around this issue by purchasing an additional battery, keeping that battery in the charger, and then simply swapping batteries when the in-camera one runs down, so there is always at least one fully-charged battery ready for use. If you see heavy use of the camera, then multiple rechargers and batteries may be the solution.
In addition, many shooters use a card reader to do image transfers from the memory card to the computer, rather than using a USB cable or Wi-Fi with the camera. In many cases this can be quite a bit faster, and does not run down the battery in the camera.