thanks for everybodys input. the client has been subdued and is allowing me to incorporate the shopping process within the main window (which means a lot of copying and pasting of code! but hey ho...)
i did have a look at modal windows, though decided against it. i didnt know about modal windows before, so that was interesting.
i still dont know why the onBlur="window.close" didnt work, but i think thats for a different post.