.
.
If you're still seeing an "image" of that error message on your screen, it means that your screen is just dimmed and not off. After the error message, (while the box is dimly visible), press the power button for about 3 seconds and see if it turns the screen back up. Then try Soft Resetting, again.

........grasping at straws here.
Also, try this:
Button Hard Reset; Press & Hold the Reset Button then Press the Power Button. This
should give you an Option Screen, with a choice to press one of two Hard Buttons (I don't remember which, but it gives graphics). On will do the hard Reset, the other is a default exit. Sometimes choosing the exit/cancel choice will allow the reboot process to continue without wiping all memory.
If it doesn't give you the option screen, you're probably gonna hafta do a Battery Hard Reset:
Remove
BOTH batteries, sling a slew of curses at the computer gods, put the batteries back in and start from scratch.
I also suggest getting
Sprite BackUp
HERE's how I have my Sprite Backup configured.