I would NOT blow out the vent or fan with compressed air. ask me how i know.
If you turn your laptop over, you will see that its pretty easy to take apart provided you have the right screwdriver(s). Place your laptop on a piece of big paper just in case those little screws get away when you remove them. Make sure you remove the battery and AC outlet before you start removing the screws. You'll figure it out. It doesnt take a rocket scientist to finally get to the fan. I betcha you will pull a dust bunny from hell out of the fan area. I did twice over the life of my 5 year old laptop.
Consider getting one of those cooling fans. Even the cheapy ones work well. I bought a metal one that's slanted upwards with three fans on it. It keeps my Dell 700M cool and this laptop is notoriously known for having a hot palm pad.