Display legal notice on startup:
Wanna tell your friends about the do's and dont's in your computer when they login in your absence. Well you can do it pretty easily by displaying a legal notice at system start up.
"legalnoticecaption"="enter your notice caption"
"legalnoticetext"="enter your legal notice text"
Automatic Administrator Login:
Well here's the trick which you can use to prove that Windows XP is not at all secure as multi-user operating system. Hacking the system registry from any account having access to system registry puts you in to the administrator account.
Wanna play with your friends by removing the shutdown option from start menu in their computer.
Just hack it down !!!
Another minor and easy tweak to remove any delay from menus sliding out. For this you will need to use regedit (open regedit by going to Start -> Run..., then typing 'regedit' and pressing enter). The key you need to change is located in HKEY_CURRENT_USERControl PanelDesktop. The actual key is called MenuShowDelay - all you have to do is change the value to 0. Remember, you will have to re-boot your computer for this tweak to take effect.
GPEDIT.MSC And Autoplay
A great tweaking file that comes with XP is gpedit.msc. Go to Start -> Run... and then type in 'gpedit.msc' and press enter. This is effectively the Policies Editor, and it comes in handy often. For example, if you hate CD autoplay like I do and want to permanently disable it, you can use this tool to do so. Just run gpedit.msc, then go to Computer Configuration -> Administrative Templates -> System. In here you can see the value 'Turn Off Autoplay'. Right-click on it and then click 'Properties'.