Biggest icons

Hi all,

I'm developing a survey to be submited to the visitors of a museum.
The survey will be apllied in a touchscreen in order to facilitate the visitors.
It's possible to put the icons (radio buttons, font size, space between paraghraphs ) bigger?
It´s because like it is now the user can make mistakes when to select the answer. The radio buttons are small and the space between lines are small..
Anyone can give me a help ou suggestion?

Best regards

Milton Aguiar