I would drive or uber. It is only 45 mins.

I'm a Californian who left before metro was put in so am unfamiliar with the system. I was looking at the "tram" from Santa Monica to the LA train station and then taking the train to Fullerton. Is this easy and doable? I'd rather not drive because we will have only one rental car, which I should leave with DW in Santa Monica. I'm used to New York subways so don't find it daunting but would appreciate some advice. I assume the return (train to LA, tram to Santa Monica) would be the same. Uber X is @ $42 to 64. TIA.