There's no field called "arthropodology" because arthropods are too diverse a group. In any case, you're way too early to be choosing a field for graduate study. Take a variety of undergrad courses and see what appeals to you. All the biological sciences are being increasingly quantified, so you'll have to become proficient in statistics and you'll need to develop good computer skills.

I'm about to start college and I'd like to do my graduate studies in arthropodology/arachnology. Would an undergrad in zoology be a good foot-in-the-door start or is there a better path to take? Thanks in advance!