drilling holes in laptop, not so good an idea, unless you know how to part that puppy out and remove the electronics...not everyone is skilled at pulling out 30+ screws and putting them all back in...
i have a 7yo laptop that works fine for me, except for compiling video or watching too many movies will cause it to overheat, so i put some lego bricks on the bottom to let a little more air get under the laptop...
if you are gonna keep that puppy cool...a good quality laptop cooler pad will get that air flowing over the bottom of the laptop where most the heat will radiate from and give you some more years on your baby...