I recently needed to remove some of those rubbish default apps you get on android phones. You know the ones, the ones that come with the phone but you can't uninstall. It is especially annoying if you don't ever want to use them and they are taking up loads of space on your phone because you have an Android version prior to Froyo (2.2) so apps can't be installed to the SD card
One of my phones (a Sony Ericsson Xperia X8) is on Android 2.1 and I want it stay on that OS, but it was running out of memory. I already rooted it some time back, and a quick google search came up with this great guide: http://androidadvices.com/remove-default-applications-rooted-android-phones/
I have one thing to add though, which is why I am writing this. Once I'd uninstalled FourSquare, Facebook, Stopwatch, Planet3 and loads of other stuff I didn't want, I was surprised that they still showed as installed. So I checked again with the article above, nope, definitely gone. But they still show in my apps and the memory is still full. Here is the solution: Go into the app manager and 'uninstall updates'. It will fail to uninstall (because the app is already gone) but now they don't display and the memory is freed. Hurrah!