Display nothing but white screen on my BlackBerry phone

Hello!
My wife and I both own a BlackBerry model phone; hers is a BlackBerry Curve while mine is a BlackBerry Bold. It has been in our possession for quite some time now but not really for long. What we have observed is that both our batteries are experiencing problems; one was about to ceased working while the other, even with still one bar of battery life already shut off. What we did was charge those using their respective chargers. However, to our surprise, both phones displayed nothing but white screens. Please, please help us with this. Your assistance will be very much appreciated.
