could use this to create the thumbnails:
http://www.fookes.com/ezthumbs/
and then i guess something like this:
<a href="/username/photos/photo_001.jpg">
<img src="/username/photos/photo_001_tn.jpg"></a>
but to be honest if you download this:
http://jalbum.net/
it generates all the thumbnails and html for you.
gary - i agree uploading to photobox is a pain.