Nikon Coolpix 3700

How do you adjust the ISO?
I don't think you can actually adjust the ISO manually. There is a feature where it will automatically adjust it if lighting is poor. The camera lets you know when it is doing it by showing a little ISO icon.

How do you adjust white balance?
Aside from choosing different types of scenes in "Scene Mode", in Manual or Auto mode, you can find the option under the main menu. Then you can choose the type of lighting conditions or set it to either automatically adjust it for you, or you can even use a gray reference object to help the camera in weird lighting situations.

How do you set exposure compensation?
You can adjust this any time by pushing the joystick to the right. This brings up a little scrollable option that lets you choose a range between -2 EV (underexposure) and +2 EV (overexposure), zero being the normal.

How do you set file size and compression?
Under the main menu, you can choose "Image Mode" and then you can select the file resolution and you get somewhat of a choice on compression. There is a 2048 Normal and a 2048 High option, the latter having a compression ratio of 1:4 instead of 1:8, or half the compression of all the other image modes. I would probably just leave it on this option, because I like to get as much data to work with as possible. Once you have the picture, you can't just increase the resolution or remove some of the compression artifacting, so I would rather not end up with my favorite photo being stuck at 640x480.

How do you set the exposure meter mode?
I believe the only way is to choose a Scene mode. The camera will adjust exposure automatically in Manual or Automatic mode, but you can use the exposure compensation to adjust it up or down slightly.

How do you set macro focusing?
You push the joystick down and choose "ON" from the scrollable menu. This lets the camera focus on things up to 4cm close.

How do you set the flash mode?
Push the joystick up and choose an option from the scrollable menu that comes up. You can basically choose On, Off, or Auto and then there are two special modes, one for red eye reduction, where it flashes a red eye reduction light preemptive to the main flash, and a slow sync mode where it automatically flashes over a long shutter speed.