Fresh install?

So, I've had my iBook for about two years now and haven't had a lick of trouble with it. But recently I've been encountering major slowdowns.

I'm thinking of just doing a fresh reinstall on this bad boy to hopefully bring it back to its glory days. What do you all think? I normally don't resort to such drastic measures but, 1) I can back everything up on my external; and 2) I think this is the quickest solution.

Does anyone have any other pieces of advice?

ibook

did my ibook which required an erase and install because the hard drive
did'nt have the room.

went seemlessly like my other macs

regards