How to reboot my wii after I updated it. It can't open the wii menu. I think the file corrupt

Try unplugging it for a minute then plugging it back in.

(Assuming your Wii doesn't start up at all)
If that doesn't work, I would call Nintendo and tell them what happened. Because if a firmware update from them did indeed corrupt... that can mean that the unit has been "bricked" meaning it's now an overpriced paper weight. They might have a solution for you though.