If you can contact the last owner, and if it turns out that they used one particular brand and weight of oil in the car for the last several years; it is often better for an engine to use the same brand and weight of oil that has been used in it; rather than to change brands. Changing oil brands can be a shock to an engine, and can sometimes lead to problems.
If you cannot find out about the oil usage history: I would go one of two ways. The absolute best oil which can be used in this car is Mobil 1 full synthetic; in only their 0W-40 weight. But it is expensive; the price has recently increased to more than $7.00 per quart, and it is sometimes hard to find in stores. Any store that sells Mobil 1 can order this viscosity, if they don't already stock it. It can also be purchased from Mobil oil distributors.
If you prefer to use a less expensive oil; I would use Pennzoil Gold Synthetic Blend in 10w-30.
I would use a Fram Tough Guard # TG6607 oil filter on this motor.