I'm struggling a bit. Am i being tight thinking there must be a bit of free software that doesn't contain adverts etc that will allow me to create simple .swf files - all i want is a simple slide show effect for a website.

http://www.adobe.com/downloads/?ogn=EN_US-gntray_dl_trialdownloads

free trial downloads of shockwave flash.

if you want really simple, i think powerpoint should be able to do something similar for you. flash can be pretty hard to work out. i used to use it years ago (not very much) but i wouldn't have a clue now...

You could make a gif movie which might be easier.