I am at the point of finish sanding a solid oak desk and would like to know what you consider the hardest varnish, urethane etc to put on the surface. It is a desk that will get a lot of use as a computer center and would like a surface that is fairly marr resistant.
Urethane finish would be your best choice. If you are happy with the colour of the oak use acrylic urethane all major paint companies will have a brand available. Building supply stores will stock Flecto Varathane or Minwax. Using a solvent based urethane will tend to give you a honey colour more like your older oak finishes. Both acrylic and solvent-based finishes will service you well.