What Voodoo said, make sure your html is correct so that the page & text is rendered first, therefore the surfer has something to read/keep his attention while images load around it.
If you wanted to be daring, i'd create every functional bit of the page in normal text/html that way if the user dosen't want to wait for the fancier stuff (images) they can just proceed, no worries.
Which is why I always make text on a button actual text, instead of being written on the button image. That way they know what the button represents without waiting for the image.
