Go to a command prompt and type "adb shell"
You should see a # sign, that's the root terminal on your phone.
In order to remove apps, you need to remount your system folder on the phone with write permissions. To do this type "mount -o rw,remount /dev/block/mtdblock3 /system" (it won't say anything it will just go back to a # sign again)
Now type "cd /system/app" and then "ls"
That will list all the apk files, which are the applications.
You can remove them by typing "rm -r Whatever.apk" (it's case sensitive)
BE VERY CAREFUL doing this. Don't just go around deleting apps. Some may not be safe to delete as they are connected with other apps, etc. Those three I posted are safe to delete.
A few important notes on this -
1. The pro version of Titanium Backup will let you freeze an app. That makes it un-runnable - as if it were deleted, just still taking up space. Many suggest freezing first to ensure no bad side effects for those tinkering around with apps, and then delete when you're sure it's ok.
2. Personally - I recommend doing a full nandroid backup before attempting anything of this sort (and yes, I've done the above myself) - and then a nandroid restore at the first sign of trouble - you might easily mis-type something and delete the wrong thing.
3. This is most important - when you delete just an apk, you're liable to leave trash in the dalvik data/cache areas that make your phone get a little wonky. (The Dalvik Virtual Machine is what makes Android Android instead of just a fancy name for Linux.)
You can clean up your data/cache areas from recovery - or by doing a factory reset. Personally, I back up the good stuff, do a factory reset, then restore the good stuff - it's way easier and pretty painless when you're rooted.
See tips on how to do that here -
http://androidforums.com/evo-4g-support-troubleshooting/141369-how-fix-froyo.html
And btw - as memory serves - you can simply delete the app from within Titanium Backup, and save the adb route - but as I mention - I've done it both ways.
Hope this helps!
PS - other most important part:
To our new and newer members I'm seeing here -
Welcome to the forums!