1 - your using a basic entry level motherboard and chipset
2 - 3x1gb = no dual channel, sounds like your using a 32-bit OS too..
3 - celerons at whatever clockspeed are still going to perform like celerons
4 - never expect your rig to overclock or gain anything - some samples will overclock like crazy, others like lemons (my old P4 2.6 made 2.83ghz tops)
read the overclocking sticky guides on the forums here and google is your friend, learn how the FSB and multipliers work first