Used to be way into buying/trading cards before I turned 21 and started using that money for my beer hobby/habit.
If we're talking early 90's... Yea, fire starters for the most part. This is when cards were produced by the millions. There's a few in there worth something, but they are few and far between. Mid to late 90's and you start getting into more limited inserts, so there could be some value there.
More recent cards have serial numbering, autos, game used pieces, etc., so they can be worth a decent amount more. There is also something called "prospecting", but I digress.
Best thing to do is to go to eBay completed sales. That'll give you the best idea of value.