I removed the Windows' boot menu with some terminal commands I can't recall now. I managed to do it, but now my Windows, instead of shutting down, I think it suspends. I still able to reboot it through.
I would appreciate some help solving this problem.
If you mean the system screen only fades out to black when you select shutdown, this is a feature of Windows 8 that enables the system to "boot" faster by essentially throwing the required system files into the hibernation file, minus your open programs, etc. it is essentially hibernation. If your system comes up with the boot screen when you start it again, that is the case. It can be disabled, although I don't know why anyone would want to. You can disable it within the power options in the CP. From the power options, click "choose what the power buttons do" followed by "change settings that are currently unavailable". Near the bottom of the page you will see a box ticked "turn on fast startup (recommended)". Uncheck it to disable.