How to keep all the data on my applications when I buy a new iPad
Run iTunes on your computer.
Connect old (16GB) iPad to computer with USB cable.
Back up iPad to iTunes/computer. Do not erase old iPad yet.
Disconnect old iPad.
Connect new iPad to iTunes/computer with USB cable.
Restore settings from old iPad onto new.
Disconnect new iPad.


Once you're sure the new iPad has everything you expect on it (all app data, etc.) then you can connect old iPad to iTunes and restore to factory settings wiping it out so you can sell it, give it away, or recycle it with Apple.