me_myself

But the problem is i cannot use the big image as background !! it has to be inside an <img> tag and the small image on top of it!!

It has to be an IMG tag?  That's stupid.  If it's going behind another image then it truly is a background, so your requirements are ridiculous.

I see no reason for doing it this way, but whatever you say... [^o)]

You will need to use absolute positioning to accomplish this then.

Best regards...