I'm sure the moderators have no problem with linking to a slideshow.
However, you are enhancing that slideshow by publicly broadcasting a copyrighted performance by Israel Kamakawiwo'ole.
It makes no difference that you may have purchased the CD the song is on. Purchasing a CD gives you the right to play the music for personal purposes only, not to play it as a public performance.
Think of it this way: If someone decorated their site with images of yours that they had copied from your site, you would likely feel that something of yours had been taken from you without your permission. You would be right and, in the music world, this is why ASCAP was formed. See
www.ascap.com. See also
http://www.csusa.org/face/music/faqs.htm "Do I need permission to upload music to my website?"
Mike