Ghostbusters is a franchise that has always had a pretty shaky history when it comes to video game adaptations. This probably stems from the fact that the series started in the early eighties, and there wasn't much developers could do to make a good game based on the series for primitive systems like the Atari 2600. Even though the NES or Master System could theoretically host a good Ghostbusters game, they didn't because the games were based upon earlier versions. Thankfully, when Compile developed Ghostbusters for the Sega Genesis they started from scratch and ended up making a fun game.
Compile is mostly known for the puzzle series Puyo Puyo and bunch of scrolling shooters. While Ghostbusters is neither of these things, there are some elements drawn from shooters. Basically, it is an action-platformer somewhat like a Mega Man game. The player can choose to complete the first four levels in any order, though they do have distinct difficulty levels, and when all are completed the final levels are unlocked.
The levels themselves aren't as linear as most platformers. Sure, there is a single start point and the levels end with a boss fight, but the levels have a few different paths, some of which are dead ends, and finding all of the sub-bosses and the end boss requires a bit of exploration. It's not quite Metroid, but I enjoy finding rewards for poking around, though finding a way that accidentally backtracks kinda sucks.
One of the most interesting features of the game is the monetary and shop system, which adds some useful weapons and items. Each level gives the player a certain amount of cash, which can be used in the item and weapon shops between stages. Extra money can be earned from opening safes throughout the levels and as bonuses for catching the sub-bosses.
The default gun only shoots a short distance and isn't particularly powerful, so the player can purchase stronger and more effective weapons, like the three-way shot. These extra weapons are really useful for defeating enemies, but they require weapon energy to be used, so the player has to be conservative with their use. For those that aren't that great at the game, the item shop offers healing items and the weapon shop offers weapon energy refills.
Even with this help, I found the game to be incredibly difficult when I played it as a child, though going back to it, it doesn't seem quite so bad. It is by no means easy, but I think this is just the sort of game that I've gotten better at since I was like eight years old, which I suppose isn't something to be proud of, but just sort of how that whole “gaining fine motor skills” and “not being a stupid kid anymore” thing goes.
An aspect of Ghostbusters that is a weird mixture between charming and off-putting is the art style. The sprites of the characters from the movie look like caricatures of the actors they are based on, which is kind of neat, but sort of bizarre and creepy. The whole “super-deformed” thing was done a lot with anime games of the era, but with real people there is just something off about it. Still, by comparison the designs for the bosses and sub-bosses are far creepier. Whether it is a palatable style or not, I like the game, and at the very least it has the Stay Puft Marshmallow Man and a decent rendition of the theme song.