I bought a USB video capture device (to record TV programs) recently and it comes with software for capturing movie called Honestech VHS to DVD 5.0 (Version 7.0 also available).
Although the software was designed for conversion of VHS to any format and for video capture, the first time I fired it up, it automatically detected my webcam (which is also a video capture device of course) and you can make a recording easily to your PCs hard drive. It also comes with an option to directly upload your videos to youtube, edit videos and burn directly to DVDs and convert for mobile devices. Btw, it's not HD but the video quality is great.
And yes it is designed for Win 7. But if you are using it on Win 8, in my case, I had to go to the site fo the USB video capture device manufacturer to download the Win 8 version of the driver and the software for recording videos. IT'S REALLY VERY EASY TO USE. The interface is so simple and straighforward.
What webcam do you have? Some webcams come with a free video capture softaware.
Debut from NCH offers a great but it's a limited trail. After the trail period, you can downgrade to free version which does the job but with less customization. Cyberlink Youcam also records pretty decent.