It could have really used a tutorial mode or at least told you how to shoot. I'm sure it said in the manual but the rental didn't come with the manual. I rented it again and ended up figuring it out. After that I bought the Dualshock Edition, it had a new mode called arrange game which gave you unlimited ammo plus the machine gun and rocket launcher in the inventory box. I ended up playing the whole game that way. I think my main weapon was the rocket launcher
I realize that was pretty much like cheat mode but I still enjoyed the game and beat the Leon campaign. Without arrange mode I don't know if I'd been able to beat it or not. I was only around 10 years old when I played it. It was kind of like playing it on story mode. You still got to experience the game but didn't have to worry about running out of ammo and getting stuck.
I did a similar thing with Final Fantasy VII back when I played it. I had a Gameshark for PS1 and used a max level code. I didn't totally understand RPGs at the time. I think I played FF7 even before Mario RPG so I wasn't familiar with the genre. I can't remember exactly but I probably used the code because I was getting my ass kicked by the first few enemies since I basically had no idea what I was doing.
So with the max level code I was able to breeze through pretty much all the fights but I still got to experience the story and I really really liked the game. Without the code who knows? I may have never made it very far into the game at all but because of cheats I was able to experience the game and it was great!
Have you ever done something similar with a game? Nowadays I probably wouldn't do this but as a kid I most likely wouldn't have been able to fully experience the games without them.
