What is the problem you are having?   does your bluetooth not work?   or your WiFi card?   you have to specify.  If your computer is working ok, I would suggest you leave it as is.  Only deal with drivers when you find something that is not working, specially since, as you say, you are not well versed on this.  

I'm gonna be doing a clean install soon, so I wanna know if I need to install all 9 available drivers under Network drivers (Or any other category) in dell downloads. Or just certain ones, and how to know which ones.

I know how you feel.  I too am somewhat confused of what I would need, but only somewhat, so someone with more knowledge may be able to help you with real details..

But no-one can help you unless you post as much as possible details about you exact system. You should have received with you computer a full listing and if you made any changes to hardware or software which affects that listing you would need to make changes to that information. Obviously not every driver listed is applicable to your system.

Wether or not you need or should do a clean install is of course your preference and you may have a very valid reason, but since you seem to know even less than I do, I would  also state your problems you may be having with your system.

There is also a need to proceed in a very orderly fashion when doing a re-install as has been voiced various times on this forum.

Furthermore have you contacted Alien Support?  If you have problem with your system and they suggest a reformat and re-install of Windows, they will help you to install the appropriate drivers.  The did for me on my original system when they stated I had to re-install Windows.

For my system specification click on my name to see my profile and you will see my information.

Hopes this helps somewhat to get you started into the right direction.

You can do as Spamfigther suggested and find that list that came with the invoice.  It should have the things you need to know which drivers to download. If not, you can contact Dell Support for the ones you are not sure about.     But why are you doing this clean install?   Does the computer not work properly?   or are you just trying to sell it?  

I would only do a clean install in the event you are having major problems.  I have had problems with my two laptops but have never had to do a clean install.  There has always been a fix for my problems.