hey is it possiable to get some of the leopard applications on mac os tiger on a 400mhz imac g3. ( like the new mail, spaces and the new ichat, would flinder and the new spotlight be possiable too?)
You'll have a terrible experience. Leopard was never meant to run on the G3 at all, so even if you can get it to work, good luck doing anything that takes less than a minute to process.
You can do it, but it will suck. A lot. IMHO the best version of OS X for an old G3 is Panther or, if you've got plenty of RAM, Tiger. Leopard is really designed with G5s and Intel machines in mind -- it will work on a G4, but even that's pushing it.