Really Weird Issue with Macbook Pro Please Assist

My mac has been behaving oddly recently.
1. Long load times where it alternates between a blue screen w/ a cursor and dark blue screen w/ no cursor. Sometimes it will load into osx after a few minutes sometimes it will force me to turn the system off and on again.
2. Excessive beach balls.
3. The computer will hardlock after it beach balls occasionally.
4. Hard drive making a lot of noise.

I rain chkdsk in windows xp and disk doctor's verify in osx and they both said the hdd was fine. Any idea as to what could be causing this?

Update: I just tried opening up vlc to update it when the spinning beach ball hard locked and forced me to restart. Upon restarted the galaxy background of leopard is present with a login screen, usually I'm taken straight into the os. It recognized when I input a bad pw but when I input the correct pw it takes me to a light blue screen for a few moments then takes me back to the login screen. I'm typing this on the bootcamp win xp partition now.

 

Run the Apple Hardware Test by inserting the Leopard installation disc into your Mac and holding the D key on your keyboard while restarting.