Unfortunately, your problem is more severe than disabling QP. Here is what I think may have happened:
- Your machine is getting squeezed in your bag, which activates one of the Media keys. These keys then start the machine, which boots into QP.
If QP is not available, not installed, etc.. then your machine will still boot and either hang or reboot into WinXP depending on what it finds on the hard disk. Either way, this can be worse that booting into QP since at least it will shut down after some period of inactivity.
Long winded way of saying you really need to find/fix whatever is causing the machine to boot (press a key?) since QP cannot boot the machine by itself.