Will using an older operating system lower your chances of Viruses?

[BenoitRen]

Not true. Patches for IE6 are being made available all the time.

For Win98's IE6? Because Win98's IE6 did not get the massive IE6 patch that came with XP's Service Pack 2, thereby separating the products on both platforms.

Bottom line is that other so-called "safe" browsers have plenty of vulnerabilities.

The count of vulnerabilities doesn't matter. What matters is if it gets patched quickly. Microsoft has a horrible track record in this regard with IE. What also matters is the severity of the vulnerabilities, which IE also had a bad track record with.

Also worthy of mention is that Mozilla-based web browsers are open-source, and that every security bug, including internally-found ones, are reported.

BenoitRen, I tried Minefield 3.2a1. It didn't accept some add-ons I like such as ColorfulTabs, Accessibar, Toolbar Buttons, so I had to return to Firefox 3.04.

Minefield builds come from the trunk, which is always in heavy development, except when frozen. It's no wonder that add-ons aren't marked as compatible with it.