If you do not want the system to ask for password when you resume from stand by or hibernation, you can disable this prompt in Windows Xp.
Note that this means that anyone who resumes your system can use it. If you need much privacy then it is good that you have this prompt working on. For those who do not need this prompt here is how you disable it.
Open control panel and open power options.
Uncheck the check box “Prompt for password when computer resumes from standby”.
Then click the apply button.