Help with Hitachi HDC-571EP camera?

I have the above camera and its rubbish with batteries, they run out very very quickly. I was wondering if you can use it with the usb cable instead, when i put the cable into the laptop it comes up with 3 options... PC, Printer or PC cam. I use the PC one to look at photos, I tried the PC cam option but the screen just goes blank. Any help would be appreciated as I don't have the manual with me, thank you.