Movies has wider ratio than our current widecreen TVs. They're mostly 1.85 or 2.35 or 2.40. 1.85 is the closest, so there will only be very small black bars you won't notice it.

BDs will never put the movie into 1.33 ratio (unlike DVDs). It sometimes transfered to fit 1.78, though that only was done with movies shot with Super35, because the movie directors don't like cropping their films. So what you see is actually the real ratio of the movie. To get it to fill up your screen (actually, why? you'll loose portions of the image) you can use the zoom function on your PS3 or TV.

Most movies that was shot on film used Super35 or anamorphic Panavision film stock. Both are framed at 1.33:1 physically.

Super35 uses matting technique, which blacks out the top and bottom to get the aspect ratio as desired by the director. The ratios can be 2.40, 2.35 or 1.85 theatrically. When transfered for home viewing, it can be opened up to 1.78 or even 1.33, which means you'll actually see more information (top and bottom) on than the theatrical version. So if the director doesn't mind to keep the original theatrical ratio, you will see it in full 1.78 (16:9) or 1.33 (4:3) without any cropping.

Anamorphic Panavision stretches the image vertically to fit the 1.33 film stock frame. When projected/transfered, they will be unstretched to get the 2.35 ratio. It uses the whole frame, so it will have better resoulution. This technique will always be in that ratio, so to fit your screen (1.78 or 1.33), the image will have to cropped, using a technique called pan & scan. You'll lose portions of the image the entire movie, and the director usually don't like to do this.

These are atually 35mm formats, there are also 70mm. There are many more film formats, like cinemascope, etc.

Digitally shot 1080p HD will have 1.78 ratio unless cropped.