If you have two different versions of the same exact program, then removing the older version makes sense however, even if you uninstalled the older version, during uninstallation, the files shared or used by the newer version could get deleted too which would require you the simple re-install the new version again.

But my biggest advise for novice users is, if there is no obvious need or problem, do not mess with anything! If everything working fine, I say leave it be.

~TL