My windows mobile died, sigh. I've played with all the mobiles in the house, but it turns out the best is my trusty old Nokia 3100. Horribly basic, but because it's so common, everything works, everywhere. Or if something doesn't, people fall over themselves to sort it out. My funky wi-fi mobile works brilliantly when all's well, but abandon hope any time there's the slightest glitch.
Of course I'm missing Bluetooth, micro SD, a screen that I can read in moderate sun but this phone just works and goes on working. It even takes Opera Mini.
Nokia, I salute you.