If you don't use hibernation on your computer you should disable it. Windows is constantly maintaining state in the background for the hibernation feature to work. So if you're not using it these systems resource, CPU, memory, and disk space, are being wasted on something that is never being used.

To disable hibernation in Vista it's really easy. First you need to get a command prompt with administrator privileges (see this tip if you don't know how to open a command prompt with admin privs: http://www.tipstrs.com/tip/1101/Admin-command-prompt-in-Vista).

Once the command prompt is opened type in the following command and hit Enter:

powercfg -h off

That's all there is to it, the hibernation feature is turned off and those system resources will no longer be used.

If you later decide that you want the hibernate feature turned back on you can repeat the process above and change the off in the command to on.