Why don't you restart the computer, plug your camera into the connection cable and the computer when it restarts should automatically find the camera when is starts up. Make sure you restart, plug in camera and turn the camera on.
When I "inherited" my parents' digital camera (they couldn't figure out how to work it, having spent a small fortune buying it), my brother (techie) insisted that I buy a USB Multi-Card Reader rather than use the cable and software that came with the camera. He says that digital camera software is notoriously unreliable. The Reader is a really cheap (under £15) piece of equipment that plugs into the usb slot on your computer and then you put the memory card from you camera into the reader. Get a multi-card one as you can then read other people's cards and the cards from any future camera's you might buy. The multi-card ones don't cost any more than the single card ones. I bought mine by searching online and buying it from an online company.