點樣將數碼相放在桌面而會變形

Either you set the wall paper as centre, or you use some software (such as photoshop) to resize the resolution before you do.

If you have experience on use 16:9 LCD or Plasma and watch TV programe, you will know that, the compress ratio will affect the display... some brand name LCDTV/Plasma will have well display.. but some display will make the people face more FAT.