[ddouglass]

First thing is if those cleaner discs were bought in Best Buy or other electronics stores they would be $10 or more. Dollar stores buy close outs stock from other stores going out of business for pennies, which is why they can sell for a dollar.
By blowing compressed air into a drive you risk two things. Blowing dust into areas which move and causing problems with motion. And damaging the laser by moving it from its precise position on the arm.
The discs are your best bet though they are not all that effective.
Most of the time it is more a dirty or damaged disc that will cause problems and less of a drive problem. By this I am referring to the read function.
As far as the write function goes it is usually the laser that will cause the problem but it isn't normally a dust problem. Unfortunately the more you use it the faster the laser wears out. When you burn discs the laser is at its highest intensity to be able to "burn" the information to the disc. This high intensity burns the laser out faster than using the drive for read. Thus the more you burn the faster the drive goes out.