Lock down OSX 10.7.5 app into kiosk mode?
You could enable the Guest account along with Simple Finder, then write a launchctl to watch for the front-most app and re-open it if necessary.

There are also a number of 3rd party products, such as eCrisper:


  eCrisper makes it easy to turn a Mac into a secure public access Internet kiosk. It is used by schools, museums, hotels, churches, and libraries to reliably and elegantly give access to web content.


xStand:


  xStand allows you to setup a full internet kiosk in a public space in a couple of minutes.


Also found this question which mentions both Opera and Chrome.