You can modify this behavior by adding this registry key at:
HKEY_CURRRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerAdvanced
add a Dword value of type REG_DWORD named TaskbarGroupSize
modify "TaskbarGroupSize" entry to be the number of windows you want open before XP starts to group them on the task bar.
A value of 2 will cause the Taskbar buttons to always group
Another tweak is to disable or enable recent documents history. This can be done at:
HKEY_CURRRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesExplorer
this key should already be present - if it isn't you'll need to add it:
Add a Binary value of type REG_BINARY named NoRecentDocsHistory
modify it so that value reads 01 00 00 00
39. Disable Tips
To disable Ballon tips in Windows XP do this registry tweak
Go to : HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerAdvanced
Create a new DWORD value, name it EnableBalloonTips, and set it equal to 0. If EnableBalloonTips is already there and equal to 1, set it equal to 0. Quit the registry editor, log off, and log back on. Voila! Your computer will stop talking down to you.