I just use the thumbnail image links and delete the ".th" from the link and get the full sized images.
[img=http://img840.imageshack.us/img840/1570/vivi201209006.th.jpg]
[img=http://img163.imageshack.us/img163/3373/vivi201209009.th.jpg]
=
http://img840.imageshack.us/img840/1...i201209006.jpg
http://img163.imageshack.us/img163/3...i201209009.jpg
I don't use ImageShack anymore really because there are a few more extra steps to get direct links to everything unless you log in. Their service is a bit shoddy nowadays.