It is probably a lot more secure to just allow it to update.
Most updates have a security patch, so may as well let it happen.
Exactly my thought... I've never encountered any problems after a Windows-Update.
However you should make sure to install the latest security patches manually if automatic updates are disabled.
It seems to me that you can not turn off the update Windows. This is a threat to the security of the computer and the data stored on it. In particular, cryptocurrency.
In general it's always a good idea to have a backup and obviously that's even more important for crypto-related stuff (your private-keys etc. should be stored in an offline environment anyway).