The scenery of this place is best viewed using a car. The town is only 7km form the airport and you should be able to rent a car from there.
There are a few car rental agencies that you will find and It is the length of your tour and the number of places you want to visit that will help you determine which car rental you choose. There are various places to see, some that are easily accessible and some that are not. A 4×4 would be most suitable for rough terrain like wildlife parks and the mountainous areas.
If you are interested in the beautiful botanical gardens then you would go for a simpler car that would allow you view much of this town as you can. George Town is quite a unique town and if you do decide to go to the gardens, just driving through this part of the city is itself is quite a site seeing tour. You do not even have to go as far as the game parks to have fun.
If you do decide to go to the game parks that means there is more to see for you. You could choose to hire a car that is provided by the parks themselves or like I said get one from the car rentals. The prices and the terms of leasing from each should help you decide. In most cases you will find that the game car has a cover charge for the whole tour whilst the rental will charge per km.
You could negotiate with some of the car rental companies though instead of renting per km they also offer a package plan that is if you are going to be renting the car for periods longer than two days. A rented car gives you freedom and flexibility. The game rental is only limited to the park area.