The secret website is utube.com or youtube.com
elseif string.find(internet.urlc, "youtube.com") ~= nil or string.find(internet.urlc, "utube.com") ~= nil then
You can put anything in the URL field, as long as it contains the URL anywhere. If you put all three of the URL's in the box, it'll go to whatever's first in the code. homepage.com > freedownloads.com > secret
I would recommend adding a way to upgrade your antivirus. I'm using real antivirus names for simpleness Like, you start off with Microsoft Security Essentials, which has the gun you see in the current version. Maybe then you can download Avast Free antivirus, or another free package that has a slightly better gun. Maybe add a way to earn ingame money to buy premium antivirus. Get an invite to a more powerful invite-only antivirus from your IM buddies? Depending on the scope of the project, a way to buy a better OS or hardware with ingame money for longer time until getting hacked?
The Startup jingle sounds 2005, the computer drawing in settings looks 1990, UI looks 1995, backgrounds look 2010.
Chat should have better integration to the UI. When closed, hide it to the tray, like sane chat programs do. Make bubbles clickable to open chat window. Have a small delay between the Online icon appearing and his first chat message.
Opening and closing
When a program is already open and you try to open it, make a new instance or focus the existing one. Also, add a shutdown option to the menu. Make it open a dialog, shutdown or restart. Just like in windows 98. If you're gonna add an easter egg shutdown to DOS, atleast implement:
sudo make me a sandwich
Maybe make the shutdown menu a save/load dialog when the game gets longer.