How do I stop Windows Update from restarting my computer in Windows 7 Home Premium?

Windows 8 users:

If you type "group policy" into the search field (Win+F) and select Settings you should turn up "Edit Group Policy" which is the friendly name for gpedit.msc.  The rest of the instructions are the same.

Well I can see that I have both gpedit and regedit set correctly to prevent automatic reboots, but this didn't work after Patch Tuesday today, I was faced with the logon screen when I switched the monitor on.

Actually, after a lot of digging around, I found out that apparently there had been a micro power outage or maybe rather a computer fault at 1:20AM, but the computer had rebooted automatically, so the 3AM Windows updates were installed automatically. They will install as a system user even if no user is logged on. This unhappy coincidence is why it may look like they were the culprit because the first thing you see is the pop-up notification "Windows Update has installed several updates."

It would really help if Windows could display a "The computer has shut down unexpectedly at 1:AM" pop-up first, because there is nothing to tell users what happened. The only mention of it is in the boot screen, which is not visible as Windows restarts automatically after 30 seconds, so the information is lost forever.

The only way to see what happened is to sort through several pages (28 pages in my case) of the system log in the Event Viewer administrative tool, which can't even be configured to filter out only the critical or error events from the View menu (although weirdly and counter-intuitively enough, you can create a customized view when right-clicking on the log name.)

I was almost about to disable the automatic Windows Update when I found out about the unexpected reboot. No alarm clock or appliance was reset in the house, so I had no idea this happened. It would be great to have the power supply unit communicate with the motherboard or Windows to log power outages, or to have the motherboard constantly test the PSU for power issues, or the CPU and GPU and all other temperature sensors logged as well, so we can investigate what happened and fix it if possible.

System: Windows 7 Ultimate x64

Edit: This is not a reply to Casandrita, just a generic post in the thread, but I could only see the "Reply" button, no "Post comment" button.

I have followed the link provided by Debra, which recommends the following:

1. Open Windows Update by clicking the Start button . In the search box, type Update, and then, in the list of results, click Windows Update.

I have Windows 7 and found that nothing relevant came up on typing "Update", but achieved success on typing "Windows Update" :)

1. In the left pane, click Change settings.
2. Under Important updates, choose the option that you want.

I choose, download and let me decide when to install ... waiting to see how this works out :) 

       3. Under Recommended updates, select the Give me recommended updates the same way I receive important updates check box, and then click OK.  If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

I agree with WriteOn.  There is nothing worse than having 2 browser sessions with 12 open tabs, containing articles one has chosen to read in the morning, disappear overnight for 'critical updates'.  As  a researcher, I can attest to the fact that that is a huge waste of time!! in addition to being infuriating and frustrating ... what was Microsoft thinking?  Makes one wonder whether or not their programmers understand how customers currently use their products :(

Excellent help!! Elegant Setup works splendidly.

Windows Stealth Updates, even though my settings indicate differently, has rebooted again this morning, whereby interrupting other settings and pretty much causing an unwanted chain reaction. It's like waking up to a thriller...

Thanks so much and much success to you!