ok it depends on what version of powerpoint you are running to some extent.
The following is a very basic run-down of how to do it generally speaking, I'm running office 2003 here I can also get 97 running on another pc, or office xp too..

pull up the slideshow in edit mode, not viewing mode.
from there go to the view menu and get the slide sorter running, by clicking on slide sorter.
from there select all slides
then look for slide transition, should be under the slideshow menu.
from there you should be able to tell it to go automatically from whatever times you put in the box...
now what you want to do is apply this to all slides. then they will advance every five seconds. Also be sure to uncheck the advance slides automatically....
umm, if this doesn't work PM me and if I'ms till up I'll see what else I can do..
