Pandemic - how many epidemic cards?
I think 4 is a great number for an easy game. If you find yourself running out of cards in the player deck, then you should really evaluate how you use those cards during the game. Discarding cards to take a flight shouldn't be done too frequently since that depletes that resource used to cure the disease. Also, work together to Share Knowledge, even though it can be challenging since you have to be in the same city as the card. Hopefully, you are playing with roles that negate some of the drawbacks I described above. If you are still having trouble, try playing with 3 and see what that does for you. After while, you'll start to get the hang of the game, and will look forward to the challenge that 4, 5, or 6 epidemic cards adds to the game.