I have a compost "pile". It is not in any sort of container. i put kitchen scraps, some yard waste, leaves and a little pine straw. should i build some kind of container for it? or will it compost without?

also, can i put weeds that have flowered in it, and if so how can i be sure that the seeds have died?

another question, I can can get horse manure from my daughter's stable, can i add this? and what benefit would i receive? also, my dogs are de-wormed,leash only house dogs, can i compost their poop (95% of my garden is perenials and shrubs. I could just by compost for my vegetable beds)?

I have heavy clay soil and can use all the compost i can get so feel free to give any advise...

You don't need a container to make compost. I make mine right on the ground in a pile. What you want is a pile at least 3 feet high by 3 feet wide, minimum. This size will generate the heat needed for decomposition. By all means add the horse manure, this will provide the nitrogen to heat up the pile, it will also be another great source of organic matter. Make sure you have the 2/3 brown ratio to 1/3 green. I put weeds flowered or not in mine. If you're worried about the seeds, just cut or shake them off, or pull them before. If the pile gets hot enough, you don't have to worry about the seeds. I would not compost dog poop for my garden. I just find an out of the way place to put it. The more organic material you can add to your garden the better.

The only thing a container is going to do is keep the compost contained, it isn't really necessary but does help keep the dog out of the compost. As Rockfish stated a 3 x 3 x 3 is the minimum size to create the environment for the bacteria that will digest what you put in, all else being equal, and its the bacteria that generate the heat as they digest the material in the compost pile. Different bacteria are working at different temperatures.
The horse manure will add a nitrogen source, mostly, and can be a good addition if the other material you have does not offer enough N to feed the bacteria that are working at digesting the carbon. Because our pets live so close to us their "waste" can contain pathogens that could make us ill. It is not a good idea, although there are many that dispute this, to put pet "waste" in your compost because of the potential of these disease organisms.

is horse manure considered green or brown? besides leaves, and paper, what else can be added to the pile to increase my brown percentage?

All animal manures are "greens".

A nitrogen source (green) is any organic material with a C:N ratio less than 30:1.

A carbon source (brown) is any organic material with a C:N ratio greater than 30:1.

That is the scientific definition. The practical laymen definition from Malcolm Beck, author of the book "The Secret Life of Compost", is this:

If you have any organic material that gets stinky, green, slimey, draws flies, etc. when it gets wet in a few days, then it is a "green". Otherwise it's a "brown".

He also states in his book, that good compost should have 2-3 times more browns than greens in it, plus more plant waste than animal waste in it. That is the way nature does it on a natural forest floor.

I shred up my newspapers for extra brown material. My piles heated right up when I started doing that. Don't put any meat or fat scraps in your compost because they will attract rodents. My wildbirds, however, consider my compost piles to be extra feeders! I also put my dryer lint on top for them to take as nesting material.

One other thing you need is water. Add enough so that the pile feels like a damp, wrung out sponge. When I'm building a pile I add water to every 6"layer. The grass clippings usually don't need any water.

thank you for all of your advice. got a sunday paper to add some "brown", read it and shredded it up. covered with leaves and watered well. I had way too much green for a successful compost pile.

no horse poop this week, DD had to miss lesson, spent morning throwing up instead...life goes on.