Undesired wake-up from suspend and stanby mode

I never use suspend. I always use Hibernate. (you can get at it from Start>Turn Off Computer>*hold shift* select hibernate) If it is in standby and you are carrying it in a case and it "comes out of standby", you could overheat and damage your machine. Now hibernate will still let you keep all your windows open, but it has no change of comming out of it because you need to press the power button, it will usually boot back in like 15-20 seconds. As per your problem, make you sure have no usb devices that may be waking it up, ie: mouse.