Granted im having to believe that its un-sandable because i cant physically see the floor.

But im guessing it probably could be sanded. Thing is you just need to avoid the drum sander around the "lump". Ive sanded some pretty nasty floors that had sorts of humps,dips ,slopes. Ive seen it all. As long as theres meat that can be safely removed it can be sanded.

You could try commerical strippers. But they are highly dangerous. Fumes chemical burns. Some nasty stuff. Some products that are "green" strippers. I havent found they work well. Nothing can beat a little elbow grease and 16g sandpaper. Lol. Kidding. Hoefully you wont need to use 16g.

No point in decorating a room with unfinished floors or possible structural issues. That's like putting wedding cake icing all pretty with swirls onto a moldy cake.

First, address the support issues that the home has. Find out why there's a hump in the floor, and what that means to the integrity of the home. Is it just settling, or is a major beam damaged and the home could collapse?

Second, address the flooring issue after the structural issue. Any floor can be sanded. Any. It just may involve a bit more hand labor than machine labor is all. And if the floor has been sanded many times, and is down to the tongue, then it may be time to replace the flooring.

Spending money on the non exciting stuff isn't fun. But, it's what you HAVE to do first.

Jennifer -
If the foundation problems have been solved, your floor should be OK to work on. If the foundation issues have not been fixed, don't spend a penny on anything until they are.

They have all kinds of dirt, grime, dust and yucky stuff on them.

I've worked on floors that I had to scrub with a commercial floor scrubber and detergent to see what the species of the wood was.

It's going to be a multi-step process, much of it done on hands and knees, so get knee pads. You will end up with a floor that is clearly old, but one that is clean and looks like it's a 90-year old floor that has been well-cared for. If you want all spiffy and brand new, you'll need to have new flooring installed.

STEP ONE - Scrub the heck out of the floor with a floor scrubbing machine that has stiff brushes. Wipe up the dirty water and grunge with old bath towels or those white terry shop towels and scrub until nothing much is coming off.

Wash the towels, you still need them.

The best machine for you is probably the smaller floor scrubber/polisher ones with two revolving brush heads - they are easier to control. Make sure they have scrubbing brush heads as well as polishing heads.

Let it dry.

What is left is not water soluble, so you go to solvents.

STEP TWO - Get some odorless mineral spirits, a couple of bags of medium steel wool, a good 5-in-one painter's tool (the scraper, can opener, etc. combo tool), and a tack removal tool.

OPEN THE WINDOWS! DO NOT SMOKE! Wear GLOVES (it's not terribly toxic, but it's a skin irritant to many people)

Starting in one corner, work along a strip of boards, dipping the steel wool into the mineral spirits and scrubbing with the grain ... use the scraper as needed to remove the crusty gunk. Wipe the boards with the towels as you go.

NOTE: The color of the wet boards is very close to the color they will have with a clear topcoat.

If you find staples, tacks or stuff, remove them as you go so you are leaving a clean surface behind you.

NOTE: If you drop the towels from this step into a tub of soapy water, you can wring them out, wash them and keep reusing them.

What you should have now is a floor that is free of dirt and grime. It may still have some patches of the old finish, but don't worry.

STEP THREE - Sanding and staining.

Evaluate the color and the surface ...

Color: it's normal for older floors to have color variations. You can easily lower the contrast in the colors if you want by using a stain that is close to the middle of the colors you see. You can go a couple of shades darker, but you can't go lighter without heavy sanding. It's easy to go redder, hard to get rid of red.

Species: what kind of wood is it? (it matters for staining)

Surface: Decide what to do about any stains and scars that remain. I consider them part of the history of the house ... the india ink spatters where the architect who lived in one house had his work table, the square traces of the old radio battery, the wheel marks from an old table or chair ... it's patina.

Clean them up as best you can, but don't stress over it. Think of all those people paying premium for salvaged wood that looks beat up ... you have it already.

Fill any large holes and cracks with a filler that matches the boards. the so-called "stainable" fillers will seldom stain anywhere near the color of the wood you filled. Let these dry.

Sanding: To get the finish to stick, you have to sand the floor, but you can sand lightly by hand.

Buy the BIGGEST rectangular hand sander you can - 1/3 or 1/2-sheet orbital rectangular sander (expensive, but try Craigslist or pawn shops) and several big packs of 80, 100 or 120-grit paper.

Sand lightly with the grain, wall to wall, then clean up the dust with a vacuum and wiping with a cloth dampened in mineral spirits. Your objective is to sand off just a tiny bit of the surface, not "get down to bare wood". It's often called "scuff-sanding, because you are scuffing the surface to get better adhesion.

If you stain, do it by the "wipe on" method, where you dip a cloth in the stain and wipe on layers until you like the tone. Trying to apply it and wipe it off to the right tone takes too much practice. Matching the medium tones in the floor is least likely to give you problems.

Also make sure the stain is compatible with your planned topcoat.

Apply the final finish: any floor topcoat you prefer, following the package directions. If you can find a topcoat that is easy to recoat and fix scratches on, use it - matte instead of shiny hides flaws best.

Remember that even "clear" polyurethanes tend to add a yellow tone - water-based ones dry with less of a color change.

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The pictures are of a bath I recently did.

I would have preferred to keep the old oak flooring, but it had water damage, and it was harder to replace just the damaged boards than to remove them all and install new flooring of that style. The room was too small and patching wasn't going to work.

The pine floor was laid down in the 1890s.

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This is the hallway ... haven't done anything to it yet, but it's fixable. I'll follow the process above for cleaning and finishing.

Here is a link that might be useful: What can be done to craptastic floors!

Try Citrus Strip to get the gunk off. It removes a lot and doesn't smell toxic.

I think you must show it to some good carpenter. May be the wood just need to be polish. That will also increase the life of your wood.