I have to say there isn't a "Cure All" solution to the browser problems, what works for one person might make it worse for another.

Techie Thing!
One thing you can do is IF and WHEN everything seems to be working OK then set a "System Restore Point" for the machine.
If things start to misbehave after you change something you can undo your changes.

Make sure that in your settings you have System Restore enabled.
Click Start - Control Panel - System - System Restore and ensure the option box (to switch off) isn't ticked.

Because that's a Windows XP thing, not a browser-specific thing. It (apparantly) sends a report to Microsoft outlining what went wrong so they've got something to work on for their next service pack or patch or even operating system.

Heard on the news on the radio on Thursday that the French government is telling everybody to use Firefox.

The "Don't Use IE" thing is about a security issue that MS say they have covered.
Apparently someone hacked IE and planted a Trojan(Virus) that could steal personal details.

As far as I'm aware (so my UP TO DATE (Stress))Virus Protection is not reporting any problems, Windows have however issued several updates over the past few days.
So Please make sure you are up to date!

What virus protection do you use?

Well I have a Router that filters via the Service Provider, that goes through the Windows Protector and then McAfee (But might be switching to Kaspersky in the near future). I also scan via 2 anti-ads,spam etc programmes.

E-Mails get the same scanning before they are sent.

I finally managed to send an actual email to Mozilla (instead of their error message report). That was about 3 weeks ago, and I've received no reply.
Sheesh, and they reckon that letters are 'snail mail'!