This is not true, as you can disable that option within Windows XP Pro, I do it all the time at work. Also, there is actually a way to speed up the response time for the Windows Start Menu by editing the registry.
First you will need to open the system registry by going to Start>Run then typing in "regedit" (without the quotes) and hitting enter. From there you want to navigate to HKEY_CURRENT_USER\Control Panel\Desktop, don't expand the Desktop folder just single click on it. The window to the right will show many options, the one that you are looking for is "MenuShowDelay", right click on it and select modify. Change the number from 400 to anything you want, the higher the number the slower the Start Menu the lower the number the faster the Start Menu, and then click "OK". Just an FYI I set my to 50 and it works fine.
***ALWAYS REMEMBER TO BACKUP YOUR REGISRTY BEFORE EDITING IT***
