create autohotkey script

I want to create an autohotkey script that blocks certain websites for a selected time. Also, the autohotkey app has to be smart enough that when running it CAN NOT be terminated unless u restart the computer manually by hitting the physcial reset button. Here the features of the app: when I hit a hotkey, the app 1. asks user for how many hours and minutes the user wants to block websites 2. user enters hours and minutes and clicks enter 3. app blocks websites that I define in the code for EVERY browser (IE, Firefox, Chrome, Opera...) in EVERY Windows version (XP, 2k, Vista, 7) (note that Firefox somehow does ignore the hosts file. Also the hosts file can be edited by users. THis should not be possible. The app has to use a method to block websites that can NOT be undone by the user externally unless he quits the programme) 4. app shows a small (transperent) countdown window on the bottom right 5. app unblocks internet sites when counter reaches 0 6. app offers settings menu via right click on the tray icon where I can a) --> edit the blocked websites --> gui opens where I can customize the URLS b) --> hardcore mode (off/on) --> in this mode the App CAN NOT be terminated when the timer is running unless u restart ur computer (note this might be a tricky problem to solve. It would have to block things like CTRL+ALT+del, "taskmgr" and block any attempt to terminate the process) here is a sample script: [login to view URL] Unfortunately it edits the hosts file which doesnt work for firefox. So you have to either figure out how to force firefox accept hosts files or to use a different method