The 2400 gets quite a lot of praise, as a good 'bang per buck' buy, only rivalled by the 2500 (but I don't think your board would support this FSB333 chip).
That seems to be one of the best prices around at the moment (ebuyer I guess?).
I think your board only supports the athlon chips up to the 266FSB 'thoroughbred' core, making the 2400 the highest it will go - although I'm prepared to be wrong about this