Check the fans and inside for any carpet particles. He may have 'suffocated' the laptop, since the fan is on the bottom and there was no where for the fan to vent. Also ask him if he dropped it at all. A floor is not a good place to store/put away a laptop.
Don't get a Pentium 4 laptop. They all have heat issues (overheating) not to mention, heat shortens the life of other components. $400-$500 can probably get you a Turion 64 or Core Duo (once Merom is released), $800 can get you a Turion 64 x2 or even possibly a base level Core 2 Duo.