Can I use my dual light/fan dimmer switch on a ceiling fan?
You should not use a dimmer that is designed to control lighting, as that can cause problems. Instead, you should use a fan speed control device, that is specifically designed to control a ceiling fan. You'll also want to make sure the control you're using, is rated for the maximum current draw of the fan you're using.

There's no real difference between the in wall speed control, and a remote speed control module. Both devices control the speed of the fan, external to the fan itself. The only difference is where the device is located (wall box vs. ceiling box).