If you can afford to stack the copper pennies and you dont need whatever total Face Value - FV that you found I would say keep them 100%. As you collect more and more you can sell them either locally or on Ebay for approximately 1.4-1.8x their face value. This essentially meens you can turn a profit - $100 FV can sell between $150-180 and maybe more in the future as the price of copper fluctuates and increases.
No one melts these pennies but there are quite a few people who hoard them for a day when they can be sold at 2.2(or more) above face value - making quite a bit of money in the process.
Bottom line, if you can spare the money, stack the metals!
EDIT: also its not a dumb question at all. If you have a question you can research it or ask someone here. Sometimes people can be a-holes but dont let them get you down. The majority of us here are here to help!