If the buckling isn't too bad you would detach the board or boards but leave in place, and add weight to flatten upward buckling, or turn the board or boards over for downward buckling and then apply the weight.
Do you mean the base board? It is better if you can remove the base board then reattach on top of the new floor. It will give you the best look. If you butt the new wood up against the base boards...
A chemical stripper is one way. Simply sanding off the wax and stain so you restain and finish is another. Be care with the chemical stripper though, it might soak into the wood and make refinishing...