Since it's for a table runner, it will most likely be washed. So first I'd make sure all the fabrics are machine washable in hot water and can go in the dryer. After this treatment all they fabrics should be usable together. My concerns would be some fibers will melt at high temps-test with an iron set on cotton. Some fabrics may have raveled a lot in washing-they'll need 1/2" =/+ seam allowace, not the 1/4" usually used in quilts. Then I'd seperate the fabrics by color, then pick fabrics you like together. Assess how much you have and decide how they might go together. I like Iceblossom's tie quilt for odd size/shape of pieces. Since it's done on a light weight foundation, I think the stretchy fabrics would be stabilized and not need extra stabilizing. They could be adhered with a fussible web-a store can help you with that.
Yes, we quilters prefer 100% cotton of basket weave and similar wt to each other, but it's not necessary. Have fun and enjoy the memories around the table as you view your old scraps.