If your computer is running fine then there is no need to update your drivers. They may be created to fix bugs or increase performance, but if you haven't noticed a problem then it's up to you if you want to take the time to update them.
You can always update drivers on your own. Open Device Manager to see a list of devices. Pick one. For example, expand display adapters to see your GPU. Now go to that company's website and look for driver updates, or Google the name of the device shown.
I always update the motherboard drivers to the latest available when I first put together a system, because whatever comes on the CD out of the box is often an outdated version, or even the original version with bugs in it. After that, though, I agree there's no reason to mess with it unless you're having problems.
Don't bother with pay programs to update your drivers. Anything you could possibly need is going to be available for free on the device manufacturer's website. Programs like that mostly try to seem useful by giving you a warning every time your component manufacturers issue a new set of drivers, but in reality you don't need 99% of them.