Microsoft releases updates weekly to improve both the functionality and security of its products. We suggest installing those updates related to Microsoft as soon as possible. Usually with updates from 3rd party suppliers, we recommend waiting 7 days, just to make sure there are no major problems with the update.
Anti-virus software checks for and eliminates threats to your data. You cannot go without some sort of protection.
Offline or line interactive UPSes are directly connected to the mains power. When the power goes off, the UPS switches on in a very short time, and supplies power. These are normally suited for home use and are cheaper. Online UPSes permanently supply power and only use mains power to charge the batteries. They offer better protection, but are more expensive.
We recommend three backup drives for servers. One connected to the server, one off-site and one in transit. These are then rotated weekly or daily as required.