I have Snow Leopard and this didn't happen before I got Snow Leopard but it started a few months after I got it. I have it set up so that when I open my laptop up to wake it up from sleep mode it makes me type in my password but sometimes when it gets to the screen where I type my password in; it freezes, I can't type or move my mouse so I have to hold down the power button until it powers off then start it back up again. I have have my MacBook for 3 years now so the warranty has run out. Please help me.