Looked at the site, I have BB and loads instantly, every link. Cannot tell you about 56K.
However is the site created on your friends PC, if it is, the faster speed, may be because all the files are in the cache, so is reading from his HDD rather than the web.
Just a thought, as I had a similar problem way back, I thought the site was pretty fast but when veiwed on another (My Brothers) PC it took quite a while to load, however not as long as you suggest.
Check the picture files to see how big they are, some graphic editing software should give you an idea of how long it will take to load, at various modem speeds.