First of all, LeafGreen.
Second of all, your team is fairly horrible. They all have moves of the same type, and would be kicked to the curb by its weaknesses.
For Venusaur dump vine whip for poison/sleep powder or stun spore. Dump razor leaf for sludge bomb or strength.
For primeape dump low kick(pointless after snorlax) and put on focus energy/bulk up. Get a stronger rock move if you can.
For lapras get rid of perish song and put thunderbolt for a bolt-beam combo.
For butterfree give it silver wind it learns it in a few levels I believe. Gust/wing attack works too.
For marowak teach it earthquake and you're set.
And finally earodactyl. Its a physical attacker but its special is decent. Keep doing what u are doing but give it hyper beam and a dragon move.
Heed my warning before the elite 4 destroys you ...
I AM NERDZ! YOU SHALL OBEY ME OR FACE THE CONSEQUENCES!