Hi Lisa,
I had great success with the Ortho products, especially the Weed-B-Gone that you attach to your hose. When used correctly it really does work. My lawn was full of clover dandelion and other things that I'm not sure of but after a couple treatments with the Weed B Gone the lawn is thriving. Once the weeds were finally under control I fertilized using a product that was recommended by some folks that run a feed mill called Tylers 12-12-12 and now my lawn is the thickest and the darkest green that it has ever been. And it stays a rich dark green with very little watering from me. I'd say I water maybe twice a month and then only if we are having a dry spell. Good luck with your lawn and hopefully the experts here will get you going.

Get a "Weed Hound" from one of your local big box stores. It is a little tool that makes pulling weeds a breeze, especially ones like dandelions that have taproots.

If there are too many and you need to use chemicals, things get a little tougher. I see you are in Zone 8, but where exactly are you? What type of grass are you going to grow? If it is a warm season grass (bermuda, zoysia, centipede, etc.) this is the time to seed so you need to get to work on those weeds. If it is a cool season grass (KBG, fescue, rye, etc) you won't seed until fall. This makes your job easier as you have more time to get rid of the weeds before seeding.

About any namebrand Broadleaf Weed Killer will kill dandelions. However, read the directions as not all types are compatible with all grass types. There wil also be seeding-after-use instructions (ie. how long to wait before seeding). Also heed the temperature recommendations for use, unless there isn't much other grass that can be harmed by applying in the heat.

I like Weed-B-Gon Max and have had good luck with it. You can get it just about anywhere.

Here is a link that might be useful: Weed-B-Gon Max

Thanks, I am in the Seattle area. It doesn't really get hot here. In fact we were waiting to seed because the instruction say you want a temp between 60 and 80 degrees which we only really get in the summer.

The lawn isn't that big, but the weeds are dense. We've had them pulled twice and they keep coming back. I think chemicals is the way to go.

I had no idea Seattle was zone 8. That is weird. I'm in hot, humid, sandy, SE NC and I am in zone 8. Totally different climates.

Oh, well. If you're waiting to seed then go ahead and blast the weeds with chemicals.

Yes, I think zone is based on annual low temps. Although it's damp here; we rarely get much snow. Generally a pretty mild climate with no extreme highs or lows.

We joke that we have no concept of humidity without precipitation. Summers tend to be warm and dry with high rarely going above the upper 80's. There is no nicer place in the US during the summer than the Pacific Northwest.
The other 8 months are another story...

I'm sending the husband to Lowes on his way home from work to pick up some Weed B Gone to try this weekend.