how can i turn off my laptop?

ive got a compaq presario v5000. i turnedit off one day and went to turn it back on and got a completly black screen as if theres no power going to it. the light is on the base and it wont turn off. ive tried holding it forever,ctrl-alt-del, esc, unplugging it ,removing the battery for days. nothing is working. as soon as i plug it in it lights up with a blank screen. ive been dealing with this for some time now any ideas?