The First Law of Driver Updates is 'if it ain't broke, don't fix it'. Normally if everything is working you want to leave things as they are. The exception is that heavy-duty gamers will usually want to update their video and sound drivers to squeeze every last bit of performance out of the hardware to get the fastest frame rates. If you're not one of those people, you don't need to update your drivers if there are no problems you are trying to solve.
Never get drivers from Windows Update. Get them from:
1. The device mftr.'s website; OR
2. The motherboard mftr.'s website if hardware is onboard; OR
3. The OEM's website for your specific machine if you have an OEM computer (HP, Dell, Sony, etc.).
Read the installation instructions on the website where you get the drivers.
To find out what hardware is in your computer:
1. Read any documentation you got when you bought the computer.
2. If the computer is OEM, go to the OEM's website for your specific model machine and look at the specs (you'll be there to get the drivers anyway)
3. Download, install and run a free system inventory program like Belarc Advisor or System Information for Windows.
http://www.belarc.com/free_download.html - Belarc Advisor
http://www.gtopala.com/ - System Information for Windows MS-MVP - Elephant Boy Computers - Don't Panic!