I've used "Orange Glo" with good results, but it doesn't last long...need to apply it about every month. Makes a nice shine though. Can buy at Menards.
If you want something more permanent, here is a very labor intensive but long-term solution...
1) Repair any damaged areas or stain any scratches, etc.
2) Sweep floors extremely well
4) On your hands and knees, wipe all floors with mineral spirits and allow to dry
5) Buy "floor grade polyurethane"...it's thick. Get a bunch of other equipment ready...such as Shoes with spikes (you can buy them just for this purpose...or buy things you tie onto your existing shoes), paper towels, a good 18" squeegee with a long handle, and a long-handled tool with a wood rectangle on the end that you can affix a lambswool mop head on, and get a few of the mop heads (only use lambswool).
6) Have a helper behind you...you'll need them to hand you things.
7) Wearing your shoes/spikes, start in the farthest corner of the room from the door. Pour about 1/2 gallon of the poly on the floor, and spread it slightly with the squeegee. Hand the squeegee to your helper and have them give you the lambswool mop. Spread the poly around to a very thin consistency on the floor.
8) Continue this, overlapping previously done areas....work your way towards the door.
9) When done, clean everything up with mineral spirits and throw the messy stuff in the trash.
10) LEAVE THE HOUSE (due to both fumes and the fact that you don't want to stir up dust, which will get in the poly) overnight
11) Next day the floors will look great.
I've done this on two houses...one of them 12 years ago and it has held up very well.
--99.92.xxx.xxx