Lifting the lid makes laptop switch back on automatically and awakes the laptop from sleep...how to disable it?

Hi,

I current run Windows Vista Basic on my Dell 1525.

When the screen/monitor/lid is up, and I press the power button...the laptop goes to sleep (without issues).

However, lets just say, that the screen/monitor/lid is folded down and the computer is in sleep mode...when I lift the lid up, the laptop automatically switches on and comes out of sleep mode. Is there a way to disable this?

I would only like the laptop to awake from sleep mode whenever I press the "Power" button, which is located above the "F8" key on the keyboard. I do not want the automatic switch on whenever I lift the lid up..

Any help would be great! Thank you!