Boot into Windows. Go Start: Run; and type;
Under the General Tab; Advanced; Tick "Enable Startup Menu", exit and reboot.
When the menu appears, select option 4; Step by Step Confirmation.
You will have to approve every line of the startup sequence, but sooner or later, your machine will freeze, and it is important to note the last operation you approved, because this is the source of your problem.
Almost certainly, it will be a corrupted file or bad driver, but you need to identify which one!