"Internet cafe" application for android

i want to start an internet cafe with tablet pc's and i need an application for android 2.3 wich to do the folowing: Starts when the sistem starts-up, automaticaly connects to the default wireless network and displays a screensaver with a photo slideshow ( photos from a folder so i can change them any time i want by connecting the tablet to a laptop ). If touchscreen is activated or button is pressed or sensor detects moving of the tablet will display a dialog box asking for an acces code. Acces should be in a file or a database on the tablet so i can change them periodicaly by connectig to a laptop. When a code is introduced, if he is valid (is in the file or the database on the tablet and it wasn't been used yet) people to have 30 minutes of acces to the tablet. People will not have acces to the settings of the tablet or other configurable options. Will be able to use only applications listed on the desktop ( internet browser, messenger, games folder, text editor, and others if needed). Also people will not be able to save any downloaded or copied file only in one folder ( public folder ) or on the memory card ( if they have one). When 30 minutes have passed screensaver will apear again and a new code have to be entered to gain another 30 minutes acces. If in 5 minute no code is entered the tablet will restart itself and all that the last user saved to be deleted.