I think sod might be the best way to go. Growing cool season grass from seed in Spring is problematic because it is very hard to get the grass established before the summer heat sets in. It is a delicate dance between the soil being warm enough to germinate the seed and then the seedlings growing strong enough to take the heat. If conditions are right you can pull it off, but more often you don't.

The biggest key is to prevent the winter annuals like chickweed from setting seed. They do this in earnest beginning in late winter when temps begin to edge back up. Roundup will take care of them but you can also keep them at bay with a regular beatdown at the hands of a string trimmer. I wouldn't do any fertilizing during the winter as the grass is dormant and won't uptake the nutrients; you will just be feeding the winter annual weeds. You have to pick between a pre-emergent and seeding; you can't do both because the pre-emergent works at precisely the time you have to be seeding the grass.

With sod, you can put it down in Spring and it will be able to take the heat much sooner and better than seedlings, provided you irrigate it properly. Otherwise, I would reseed in late summer/early fall when the seedlings have the best chance to make it.

If you have not applied a fetilizer to the lawn by now you should wait until spring. Possibly those that areas were seeded in grass appeared to die during the summer, probably due to no water, may very well be dormant and not dead. Grasses in our area of the world tend to want to go dormant during the normally hot and dry summer, and they usually perk up in the fall when both the temperatures and rainfall become more moderate.
Spraying any all plant killer now, or even any "weed" killer, would pretty much be a waste of your time, energy, and money since most all plants, in our area of the world, are going dormant for the winter so they would not soak in those poisons.

This post was edited by kimmsr on Tue, Dec 4, 12 at 9:08

Thanks to mistascott and kimmsr. I appreciate both of your replies. I think I'll opt for the sod next spring and get the pre-emergent going again in early spring. I'll likely contract for this work and will rely upon the contractor for the appropriate timing. I probably have less than 2000 sq ft to take care of. I think I can manage the rest of the lawn with spot treating and maybe a couple more sod strips in a couple of small areas. Thanks again for your help.

The one thing the contractor cannot do is make sure the sod establishes well. This will require keeping it pretty much soaked at all times for 2-3 weeks after you put it down so the roots can establish. Usually, the Spring weather doesn't dry the sod out as fast as Summer weather so Spring is the ideal time to do it. Even in Spring, it requires several hours of watering per day. Double check your sprinkler coverage too so you are sure it is all well covered. Good luck!