Is all good duo797, no need to be sorry, we are all here to learn.
Anyway, I had also looked into the dictionary and both verbs stand for "use", but my guess is that "使う" is more use for something like using a chopstick (to eat), pen (to write), towel (to wipe), etc. While "利用する" is for something like "make good use of the money", "use someone for personal interest", "use a cellphone to call someone". But I could be wrong, just my guess.