Several of the built-in drawers in our old house have wood slides.
They tend to stick making opening the drawers jerky and difficult,
particularly if the drawers have heavy contents in them.

I would like to fix the drawer slides ideally without replacing the
slides.

What is the best way to improve the performance?
I plan to start by cleaning & sanding the slides and fixing any
loose/broken pieces.

I assume that some type of polish would also reduce the friction. If so
what would you recommend? Johnson's Paste Wax? Something else?

Any other standard things to do to fix up wooden slides?

I'm assuming there is no benefit to replacing the wood itself, assuming
that the slides are intact and that I can sand them down.

Thanks