Pat, this is a difficult question to answer because there are a lot of different defects that look similar and yet are very different. And after you get the defect back to level, you have the problem of blending the color and shine so that it is not noticeable. However, I do have a couple of general comments that might be some help.
For light dents, a fairly damp cloth put over the dent and then gone over with a household iron will sometimes remove the dent.
A shellac burn-in set, available at places like Woodcraft, who also does mail order, does a great job on small gouges and chips. This is easier to use on a horizontal surface than a vertical one, but it can be done. Start with a lighter color shellac stick and use the "magic marker" stain colors available from Minwax and tone sprays to blend the color to match. Use a small sanding block for small areas (scraps of 3/4" plywood work great), and use fine grits (400 or 600 wet or dry) and a light hand. You can easily end up having to "fix" a lot larger area than you started on.
Most of the oak used for moldings is red oak, not white oak, and will have some dark orange to red tints in it, along with some tan or light browns. Matching the degree of shine on a final spray lacquer spray will help the blending a lot. Don't forget to mask the walls and floor around and under the moldings and use newspaper or cardboard for large areas.
The only television shows that have anything like this are some of the early "The Furniture Guys" shows, but you have to wade thru a lot of other stuff to find one where they are showing how to do something like this. But it does help a lot if you can see something done before you try to do it. Anything that shows blending repairs into other areas will be some help. Henry in MI