Speed Up Disk Access by Disabling Last Access Updating in Windows XP
 

Did you know that Windows XP updates files with the last access update time when they are opened by any application? Seems to me that it's not entirely useful, so let's go through how to disable it. Note that this tweak is not necessary for Windows Vista because it's already set as the default, even if you upgrade from XP to Vista.

http://www.howtogeek.com/howto/windo...in-windows-xp/