Can I play Wii games with my gamepad/pro controller or do I need to buy a Wii nunchuck?
Wii Mode is on the start up screen. Click the icon and it will take you to Wii mode.
Pro Controller can be used on the following games; ZombiU (Multiplayer) Call of Duty: Black Ops 2
You cannot play Wii games on the GamePad or with the Pro Controller. You can play some virtual console games in the future on the GamePad. Take advantage of the .30 sale for virtual console games. You will need a nunchuck to play games like Skyward Sword, Galaxy, etc.
I included a link where it tells you what games use the Pro Controller.