Why can't my 42'' plasma widescreen tv display widescreen tv?

ok so i've got a panasonic viera 42'' and i'm watching gillette soccer saturday but the ends of the screen i can't see! why?! is there a way to adjust the screen o fit the whole picture in. i know how to make the picture smaller but the cut off points remain the same with just a grey background. i thought if you pay �380 for a hd ready 42'' tv u could expect at least widescreen. please help! cheers.