What is the best CPU for my Asrock mobo?

ASRock K7VT4A+ Platform: ATX Form Factor: 12.0-in x 7.0-in, 30.5 cm x 17.8 cm CPU: Supports Socket A (462 pins) for AMD AthlonTM / AthlonTM XP / DuronTM processor Chipsets: North Bridge: VIA KT400A, FSB@333 MHz South Bridge: VIA VT8235CD, supports USB 2.0, ATA 133 Memory: 2 DDR DIMM Slots: DDR1 and DDR2 PC3200 (DDR400) [...] http://bit.ly/mg8nEQ