cleaning macbook

hi all, so i just bought my first (used) macbook and i want to keep it for at least a year, ok, i know computers can die blaa blaa.

my question for the forum i open it up and give it cleaning (air) i found dust in the screen, where the battery, memory and hhd sits; am thinking the prev owner had the lappy around construction or a renovation, looks like dry wall, i could be wrong.

so should i open it up and give a cleaning or have someone else do it. opening up the lappy is not a problem for me, i already changed the hhd and ram (too easy). so any info would be great..

thanks