I can't do anything on my mac! pls help!

[splintercell87]

i have mac osx 10.2.3
it is 5 years old.
i think there is a virus on it.
my disk drive wont open [whenever i press the eject key, the screen goes blank and then goes back to normal]
none of my applications will open.
only my system preferences opens.
the bar on top is transparent.
what the hell do i do?

 

[TimJim]

My guess it not that it has a virus, it's probably just that it's old and the hard drive and all the other mechanics are run down.