First a couple of questions:
(1) What percentage of charge does the computer show after say 2 Hours charge, with computer off.
(2) Will the computer power on with just battery power.
(3) do you have a 2nd charger.
(4) do your batteries have a self test. My old compaq batteries had a test Button (not really a protruding button you could depress (Used finger nail) and had 4 led lites that indicated charge state (Not all batteries have this)
Some comments.
(1) If the Batteries will at least power on with just the battery, power on, stop boot process ie Hit F8 and select dos prompt, or if possible just let it sit waiting for a response. Run battery down untill the computer turns off. then try recharging the battery...