Grabbing a webcam image from a website

I want to grab a series of images from a webcam running on a public website

What I've got so far is:
load the page into a webboresercontrol
grab the whole screen and load into a picturebox
save to file

I do this every 10 seconds or so within a one hour time period

This works fine on my work PC but on my laptop at home (vb installed) it crashes after about 5 minutes and on the desk PC (vb not installed - running app as an exe) it crashes after about 3 minutes

Is there a better way of doing this?

Thanks