Buying Bitcoins (the newbie version)
This page aims to be the best resource for noobs to understand how to buy Bitcoins. The existing Buying bitcoins page is too complex, and not noob-friendly.
You can't reliably buy Bitcoins using Paypal or credit cards. There are several ways, depending on your location.
Finding a direct seller
If you can find another person that is willing to sell them to you, you can transfer him money via whatever method (including Paypal), and he'll send you the Bitcoins. One place to look for people willing to sell is Bitcoin OTC.
Depending on your country, you might be able to simply walk into a store and buy them in the usual way (Cash/credit card).