My lawn is ~6 years old, was new when I bought the place. It looked
pretty good initially, but later I realized that the ground where the
sod was placed didn't have good soil at all. Pretty rocky, and had a
heck of time planting a small tree (which looks sickly and isn't
blooming much flowers at all).

The lawn now has a lot of dandelions, I mean, a lot. I used one of
those extraction tools from Home Depot. It does a decent job, but the
roots are rarely taken out completely, and there are just too many.
Too many to even use weed-b-gone selectively.

So, I'm thinking of redoing the lawn, probably in the fall, and need
your help. I'm thinking I need to
- Till up the ground
- Kill the existing dandelions/weeds with...?
- Put in good soil
- Put in new grass (hydroseed? sod?)
(I know I need to do more studying on it, but need to discuss it with
a neighbor that shares the lawn in this 2-family home, so basics would
be sufficient for now.)

My questions are...
- What tools do I need, if I do it myself? I only have basic
gardening tools. Rent a rototiller?
- Is there a way to get rid of existing weeds without using chemicals,
once the lawn is dug up? Cover it up to choke it? We've got dogs and
young children.
- If not, how long would it take for it to be 'safe' for dogs and
children? It'd still be a dug up ground, but you know how kids are...
they love dirt!
- Would I be better off hiring someone? (I know that's a very
subjective question...)

I'm in New England and the lawn get a lot of sun. I don't think I'd
need the soil analyzed, since whatever is there is just almost rocks,
and I'd be putting in new soil.

I'd appreciate any help.