I've had Netscape 4.7 hang a lot on my systems, but never as badly as you say, never to the point where the process can't be killed on NT.

It'd have to be behaving quite badly in order to hang the task switcher on NT. There's very little I've ever seen that'll do that. Wow.

The hangs in Netscape are one reason I switched to using IE a while back. I know your problem isn't in the browser, it's in the mail component. And switching to a Microsoft solution means Outlook, and I avoid Outlook like it was the plague.

As Mail clients go, I prefer to use Forte's Agent. I'm using a pretty old version, too. It's rock-stable, pure Ascii with no scripting (so not chance for email viruses), and incredibly configurable.