Sure, very simply. If you want to turn off your data plan, go to the home screen, then Settings > Wireless & Networks > and UNcheck Mobile network.
I suggest adding buttons to control this your home screen for quick use.
This can be done very easily by holding your finger down (aka long tap) on the home screen where you want it, and then choose Add Widget, scroll down to Settings (...), and then choose Mobile Network. Repeat these for Wi-Fi, GPS, Bluetooth as needed. You may also want to add one for Airplane Mode which is a fast way to turn off your (though airplane doesn't disable GPS).
Airplane mode can also be accessed by briefly holding down your on/off button while the screen is active.