If the structure of modern Webpages allowed it, I'd go back to Lynx and Gopher in a heartbeat. Lynx was the shizzle.
And thus the triumph of style over content... Pixel-perfection and fancy graphics that don't work at all without is not the aim, but the number of man-hours that have been spent to bend style code to ensure that as many different browsers render it exactly the same, as opposed to making it merely flexible with a "sliding windows" method... And then they completely don't work if you view with any zoom-level at all. (I speak, in this latter case, as someone who occasionally assists the elderly start to use computers and, as you might imagine, occasionally they find it useful to have larger text in their browsers
on top of reducing the whole-desktop screen resolution...)
I'm not sure if the first browser I used was Lynx (on PCs and various VT100esque text-only terminals) or Mosaic (on X Windows graphical terminals), but I used both quite regularly in the very earliest days of the web[1]. And also Gopher slightly before that, albeit mostly for frivolous stuff, like finding out the bus time tables for Wollongong University.
As a datum point, I'm currently on FF3.0.7 and it's not pestering me to upgrade. (But my Thunderbird 3.1.9 does suggest to me that
it wants to update, but last time I updated it ruined several things, so I'm holding back for a while.)
There's several things about IE9 I don't like (and I configure IE8 without all the MS-built 'accelerators'), but then I'm a bit of a technoluddite about some things. But for a lot of people using a half-way competent freeware non-MS solution would be the best answer to dealing with most computer tasks, compared with whatever solution MS provides (premium or otherwise). By that philosophy, avoid IE. Beyond the FF brand that the OP doesn't want to stick with, however, I really have no particular reason to suggest any of the obvious alternatives. Chrome just doesn't do it for me, but I can live with both Opera and Safari. The "smaller browsers" (beyond the first page of five in the Select Your Web Browser(s)[2] thing that MS gives us) might be worth a look. They'd be glad of exposure, at the very least.
[1] Do you guys remember the "Netscape Incompatible" phase, and then nice ol' Microsoft saying it would give its Internet Explorer away for free..? Mind you, I think I decided it started to go downhill about the time of DHTML's wide acceptance. And, yes, I know that a lot of the features of this post-editing field rely on some of the things that I have just decried. I'm just rollin' with it...
[2] Which annoyingly pops up on machines you upgraded to an IE8-level of Windows Updates even
after you've installed and set as default something like Firefox. And the number of machines I've seen brought into be repaired (generally for virus downloads) which as well as IE have also had their owners manage to install Chrome, Opera, Safari, Firefox without even knowing that they had done so... "So, which browser do you normally use, then?[3]" "Browser? What's that?"
[3] Have to ask this, because even if Chrome is set as default, they tend to still use the IE icon in the quicklaunch bar to open "BT Yahoo" or "Sky" or whatever home-page their ISP's normally unnecessary 'broadband installation' software has set their browser to and which they assume is both the name of the program and their only portal on the Internet. "Internet Explorer - Provided by NTL Broadband", indeed... Internet Explorer was already there, it was just rebranded by a quick registry entry change! Sorry, this "grumble grumble, mutter mutter" could go on into several more fetenete if I don't stop right here...