If i were a game developer in the 1980's my type of game i would design would be a 2d side scroller game. Slide scrolling games were the most played games back in the 80's many various title's are Mario, Sonic, Donkey etc...

I have played 3 different games from 3 different decades, Super Mario from the 80's, Zelda: Orcarina of Time from the 90's and Call of Duty: Modern Warfare 2 from 2009.

As you can imagine since the technology for gaming consoles improve in time so do the games, so you can expect quite a difference in these 3 games. Super Mario is a classic 2d side scrolling game, it has basic game mechanics and environments, the art work is pixelated which is way back in the 80's the designer did not detail the main character mario so much because of the limitations of graphics.

In Zelda: Orcarina of Time you have an 3rd person prespective on your character, an open environment to roam, 3d object and more interaction with objects and A.I(Artificial Intelligence).
The Environment and textures of objects, buildings ,etc are more detailed than 80's game and still not outstanding compared to todays games. The good things about Super Mario and Zelda is that the story is simple and basic to play which i think make both the games fun in nowadays.

To present day games like Call of Duty: Modern Warefare 2 there are more ways to move your character considering that since console evolve so do there controllers, take an Playstation 3 or Xbox 360 controller and compare it to an Nintendo 64 controller or Super Nintendo. There are alot more button's and 2 analogue sticks, which mean the gameplay will change because there are alot more precise controls because you have control of the x, y and z axis when moving and because of more buttons means more interaction with the player.

The Environments are also way more detailed because most modern day console and pc players are screaming for more detail and better graphics, CoD: MW2 also is an FPS.