i850 ringtone help

i just bought an i850 and i understand that it can handle mp3 ringtones. I am wondering what bitrate to convert my songs to in order for them to be compatible.

I was also wondering if the wav ringtones still have to be 8bit, 8000hz, mono like with the i730.

Lastly, does anyone know the resolution of the part of the screen not covered by the bottom bar? (or just how many pixels (vertically) the bottom bar is and i can do the math)

thanks,
mobob