Disable Balloon Tips in the Notification area

Balloon Tips are nothing but pop-up notifications of certain events. Some examples are the "Network cable Unplugged", SP2's Security Center Firewall or anti-virus alert messages etc.
You can disable these balloon notifications using these steps:
1. Click Start, Run and type regedit
2. Navigate to the following subkey:
HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ Advanced
3. In the right pane, create a DWORD value named EnableBalloonTips
4. Double-click the new entry, and give it a value of 0.
5. Quit Registry Editor.
6. Log off Windows, and then log back on for the changes to take effect.
Using Tweak UI Power toy for Windows XP
Tweak UI helps you automate the above. Download Tweak UI and install it. Launch Tweak UI and click the Taskbar and Start Menu section. In the right-pane, uncheck the option Enable balloon tips.