No, you shouldn't need to clean the lens regularly, as the spinning of the disc will tend to blow any dust away from it.
The best way to clean a player when problems such as skipping or failing to read the discs Table of Contents occur is to unplug the player, take off the lid and clean the lens with a cotton bud moistened with isopropyl alcohol. The bud should be barely damp, and you should use as little pressure as possible.