To the advice already given, which is excellent, I'd add:

1 - Get your soil tested. Look in the county listings for the Rutgers
agricultureal extension service. You can get a soil mailing kit from
them and they will test a sample for about $10. There are also DIY
kits at garden centers. Test both the front and back. That will tell
you what the PH is and how much lime you need to adjust it. Also, take
a look at the soil that is there. To grow a good lawn, you need at
least 6 inchs of good top soil. If what's there is really bad, you;ll
have to fix that first to have a good lawn.

2 - Don't listen to the neighbor that says you need to overseed every
year. That should only be necessary is something has happened to kill
the grass so that it is thin or has bare spots. If that happens every
year, something is very wrong.

3 - If you do need to overseed, rent a slice seeder, which is the most
effective and easiest way, and do it early Sept. Apply a starter
fertilizer at the same time and then follow up with a winterizer
fertilizer in mid to late Oct.

4 - The Scotts products are excellent, but probably not worth the extra
money compared to a lesser known brand. And as was pointed out, I
would not get into the 4 step program. For weed control, once a lawn
is in good shape, for a typical lawn, all that you should need is to do
some spot weed treatment with a 2 gallon tank sprayer, when necessary.
For fertilizer, I'd do it once in the late spring, with a product that
include pre-emergent crab grass control. Then again in early Sept with
a regular fertilizer, and then again in mid oct with a winterizer.