Pooka - the only drivers I update regularly are my video drivers- and even then I have been known to roll back to older ones . If you have an older video card then the driver updates might not be any good for you as they are optimised for newer models.
If you are not having any problems then I would not touch my sound card drivers, mobo drivers etc, however if you are having crashes to desktop then this is a possible cause of conflict
If it is programs then again if they are working fine Id be tempted to leave well alone , or go to the programs home site and read the info on the update prior to installing- most reputable programs will detect an older version and give uninstall instructions or install over the top by themselves
just my thoughts mate
S