Guarding against malware-loaded fake updates
Yes, fake program updates can be, and have been, used to install malware on unsuspecting users' systems. I know that Adobe and Mozilla updates have been faked, and there probably are others. However, getting a lot of updates from Adobe is normal as they must continually patch the many security holes in their programs, so this in itself is not an indicator of a problem. But as they have been faked before, it might be prudent to be careful.
Protecting yourself from such scams is rather straightforward. First, do not allow automatic installation of updates - only get notifications of update availability. No knowledgeable user in any of my circles allows automatic updating. It is not just a matter of security, but we want to know what each update does so we can choose what to install and avoid unneeded or unwanted patches.
Second, you should not install an update directly from the notification unless you are absolutely certain the source is legit. Instead, go to the program's main site and check the currently available updates. If any you need are listed, download and install them from there. While this is a little more work than using automatic updating, it is the surest way to keep fake updates from installing trojans or other baddies.
Do your antivirus programs provide protection from fake updates? No antivirus or antispyware program is perfect - so no, they may not provide all the protection you are looking for.
You say you have several antivirus, antispyware, and firewall programs running on your computer. I hope that only one of each is actually running to provide real-time protection - running multiple antivirus programs concurrently can cause problems. Choose one to be running in real-time protection mode and set the others to run only when requested. Then, if you suspect that malware did get through your real-time program, scan manually with the others. For example, I currently have Avast running as my main antivirus and antispyware protection. I then periodically run MS Security Essentials, Malwarebytes, Superantispyware, and sometimes the online Housecall, to find things that Avast may have missed.
Hope this answers your questions.