I know a lot of people who have very strong views against Catholics and was really starting to wonder, just as the title suggests, other than Catholicism having priests, what differences are there?
The question makes the assumption that "Protestantism" is easily defined, and can easily be compared.
"Protestant" simply means "Not Catholic or Orthodox", and could refer to one of hundreds of different denominations, all with subtle and not-so-subtle differences in beliefs. Some hold doctrine that is similar to Catholic doctrine, and some that is vastly different.
There's a comparison chart of Catholic to Protestant views here, but as I said in the above paragraph, on the Protestant side, there are a wide range of beliefs, and this chart only shows one particular protestant view. (Glancing at it, it appears to be a Calvinistic point of view.)
An entire book could be written on this subject alone, but some differences include:
In general, your question can be answered as "yes, there are some significant differences between Catholicism and Protestantism", but the difference varies based on which Protestant denomination you're referring to.
David Stratton pointed out a few of the differences. A very good answer, but missing a bullet point on Mary, but this answer isn't about her. The most significant difference ought to be pointed out specifically. It is the Real Presence of Christ in the Eucharist (What he's talking about as Transubstantiation).
Because of the priesthood, these differences are shared between any Catholic/Orthodox congregation and any Protestant denomination.