To download the pictures you need the driver for the camera ...this can be downloaded from the support site if you do not have it ..but from what you said it seam that the issue may be of other cause..
The camera need to be powered and on ..in the moment you connect it to the computer ..and also you need to confirm the pc connection from the camera in the moment you connect ti .make sure you have its driver installed .
Try to connect in a different usb port ..cause even if the driver is missing the computer should react on the usb device being plugged and ask for the driver.
If no port will react ..try the camera oin another computer ..and like I said always make sure it is powered and on ... If it makes no reaction in another computer ..than something is wrong with the camera .Another method to download the pictures..is to use the card from the camera directly into a card reader and copy the pictures from it ..
here is a link for the driver if you need it ..http://esupport.sony.com/US/perl/model-home.pl?mdl=DSCW370G&template_id=1®ion_id=1&tab=download#/downloadTab
this is teh picture browser it uses...be sure you select the operation system you run ..and also make sure you download the full program first and the upgrade after ..cause the update download may not work without the original one ..(down on the list ) ..
Good luck !