Alarm for Service: Windows Update continually going up and down

Probably will need to take a look at some of the admin guide documentation for SAM if you are new to the product.  You would just need to edit the template to disable or remove that monitor.

Manage application monitor templates and component monitors - SolarWinds Worldwide, LLC. Help and Support​

As far as the main issue you want to address, how would you see if a server has pending windows updates normally?  Windows Updates were never my primary job but I would always assume that the WSUS server was the best place to actually track that stuff, not sure how you would efficiently check from the host itself.

Some quick googling indicates this might be a powershell script that you could re-work to track that stuff but its not exactly a one liner.

Finding Pending Updates Using PowerShell -- Microsoft Certified Professional Magazine Online

These posts may help you with how to modify that example to give you a count of pending updates you can track in SAM:

The Basics of PowerShell (part 1)

The Basics of PowerShell (part 2)

The Basics of PowerShell (part 3)

In addition to the link Marc provided, be sure to check out the Windows Update Monitoring section of the SAM Template Reference​. That landing page also includes links to training resources for SAM templates, including videos and SolarWinds Academy classes that are free to all customers on active maintenance. The SAM Getting Started Guide may also prove useful.