What do you mean by widescreen? The very simple answer is that you get three types of 'widescreen'
1) black lines are added at the top and bottom to cover the image. You will effectively lose further res in post production if you crop and expand.
2) the image is cropped and expanded inside the cam to use the full res.
3) the size of the CCD is expanded to capture in true 16:9.
Most cams in your price range will do 2 above
see this resource: