Are they light or dark wood floors?

Totally depends on the vibe you are shooting for. Could be stone, slate, cement, drywall, plaster, steel (raw or stainless) or even wood.

I think it would look cool if you just stripped the marble tiles off, left it the normal finished drywall on the side, and painted the wall a bold color. It depends on what your decorating scheme is for the rest of the house, but I think just paint is probably easiest (also coordinates well with what seems like a lot of glass).

Great windows - looking out on a chain link fence.

Get rid of the fence.

I'd have the fire place be plain white wall board, no mantle.

Hardwood floor.

I love your windows!!!!

Check the builing codes, but, I think you have to have a non flamable material surrounding the fireplace. I think a lighter stone would be better, but not all the way up the wall. Also, I don't like the way the stone flooring goes all the way across to in front of the door. I would use it only as a "hearth" and even raise it a bit, and have a separate piece of matting/carpet on the inside and outside of the door.

One huge piece of travertine...

I recommend painting the wall bright white, not using a mantel, and maybe adding a black granite floating shelf under the firebox (as a modern hearth).

I say avoid stainless, I think it’s a fad on it way out. In two years it will be as cool a suburban tract house.

If those tiles were actual marble, I'd be tempted to just keep it as is. I kind of like the look. But seriously, if you're going for wood floors, I like the look of slate for this, because it's natural and potentially kind of colorful and variegated but still modern. And then I'd probably do a very simple mantel.

depending on the shade of your hardwood flooring (lighter, darker, variegated) you could choose a variety of materials for the fireplace.

I would avoid adding a mantel, and suggest adding a raised portion of the floor directly in front of the fireplace as a kind of extended hearth (something deep enough even to perch on?) with wood storage underneath or to the side.

I like the idea of stone, still somewhat rough-cut, on the fireplace and the hearth. It would be nifty if the raised hearth stepped down on the side to the doors in the picture - you could have some very attractive wood storage next to the doors. If you were to do that, I would push the material all the way across the doors to the wall, and not leave that 18" or so gap between stone and wall.

Thanks for all of the creative suggestions. We haven't moved in yet so it's a bit of a clean slate... and these posts have expanded our ideas. The chain link is def. on the way out. And hopefully we can find an affordable alternative to the wobbly screen and sliding door to the right. We haven't selected a wood floor yet but are hoping to find a medium honey brown color that will work on a slab foundation. For the fireplace -we're double-checking but I think you have to have approx. 18inch of non-flammable material in the front. Right now we are leaning toward slate or something similar because as curtis notes it's "natural and potentially kind of colorful and variegated but still modern." And ideally, it will anchor the space a bit more than plain white walls.

stainless steel and white marble

Do not put more tile down afterremoving what's already there.

I would go with terrazzo floors or really white/light floors or really dark/black wood floors.

I love the straight lines of the architecture. To compliment them, I would build a solid-line mantle above the fireplace.

I'd open up that section of the wall and put in a cylindrical steel chimney /smokestack (ideally, a facade around the exisitng one) and fill in the rest of the space with clear glass. If you want a mantle, a thick glass shelf would look good, I think. Keep the firebox flush with the wall.

In any case, I'd try to work in more clear glass rather than keep it closed up.

Good luck!