Most companies use Nematoes as a treatment for grub control. The problem with that is that they are so tiny they are invisible to the eye & I always have a tough time paying for a treatment for something I can't see, you basically take their word for it. Canadian Tire sells Nematoes in a sponge format that you spray on your grass through a hose & jar combination, I'm never sure how well it works. Corn glueten now seems to be the treatment for weeds since the pesticide ban & it works okay.
Personally, I like to aerate my yard every spring. Every other year I throw a load of top soil after aerating the lawn & throw some seed around. I fertilize the lawn about four to six times a year with a combination of fertilizer & corn glueten. I buy the corn glueten in pure form from Ritchies & mix it with a good Scotts fertilizer. Scotts IMO is the best & they also sell a combination of fertilizer & corn glueten in the same bag. Corn glueten if put down in the early spring is suppose to prevent the weeds from starting. You will still get weeds but hopefully less, pulling them out or using a weed spray also helps to control them. I use corn glueten mixed with fertilizer throughout the Spring, Summer & Fall. If you continue to feed your lawn throughout the season it will keep your lawn thick which will keep the amount of weeds down, however, you will then need to cut your grass more often. Can't win.
Keep in mind that it's not cheap & that I can spend a few hundred dollars each year for aerating, earth & fertilizer & it can be a lot of work. If you have a truck you can rent an aerator & pick up dirt yourself to keep costs down a little, Carp Road has a place that sells earth. Ever since the pesticide ban most people are having problems with weed & grub control. Oh, some companies now have something called Hyrdo Seed, I think it is, sometimes you can see it on the sides of roads that the city or townships use. It almost looks like a green foam which is laid over the lawn & watered regularly. You may also want to consider an irrigation system to assure you water the grass on a regular basis which is probably the key to nice grass, watering regularly but they are not cheap either. Good luck.