Those particular add-ons are plugins, and the plugin check page usually will flag the ones that need updating:

https://www.mozilla.org/plugincheck/

However, it's definitely not perfect.

For Adobe Reader, last time I checked, Adobe wants Vista users to stay on the Adobe Reader X series. To update Adobe Reader, I suggest using its Help menu, Check for Updates. This also will refresh the browser plugin if needed.

For Java, you can use this page: http://www.java.com/en/download/testjava.jsp

For Flash, you can use this page: http://get.adobe.com/flashplayer/ (detects current browser)

For both Java and Flash, keep an eye out for unwanted extras and uncheck the boxes as needed.

Footnote: The plugincheck page doesn't check your IE ActiveX controls, so if you every use Flash in IE, you'll need to handle that update separately.

My plugin page says they are up to date. There are some "unknown" plugins but only gives and option to research them.Don't know what that means

Hi cawlady1, Mozilla gets updated plugin version information from some software publishers. When it doesn't have that kind of information, it will show a research button.

I guess if there is a conflict between McAfee and the plugin checker, you may have to see where McAfee's link takes you to figure out why they're different. I don't use McAfee myself.