My battery recharges but doesn't hold out very long. The battery indicator light, the LED blinks three times amber and one time green. Wondering if the battery needs replacing or is there something wrong with the PC. Any clue?

http://support.dell.com/support/edocs/systems/ins1150/en/F7573a01.pdf

Page 32..

My interpretation is the Green is because you have AC power to it and the rapid (Yellow-or-Orange) is because the battery is shot.

Correct with laptops batteries they can go bad if not used. If you have a laptop but never unplug the AC from it then you're not using your battery so it causes them to get "shot". I would visit the link in the above post it looks informative.