Reviews on this site are rated on a scale from 0 to 5 with 5 being the best score. I use a led bar system to indicate the score each game received .I rate each game in 5 categories (listed below).

=0 This is the lowest score possible. Something must be REALLY bad to get this score

=1 Like the previous score something must be REALLY bad to deserve this score But something is good enough to keep it from scoring lower.

=2 Below average score. Their are several problems but a few redeeming qualities in this title.

=3 average score. most games will get this score unless real work was put into it.

=4 above average. This is given only when quality features are used. This is a game worth playing.

=5 few games will ever get this score. This is either a classic already or is destine to become one.
Graphics overall look of the game. This includes the layout and speed the game runs at.
Sound This includes the FX and music. I'm looking for quality sound not just more of it.
Control What good is a game if you can't move or move the way you want!
Fun Highly objective. I give high scores to any game that remains a challenge evan after mastering the game
Overall a rough average of the above scores. I do use my judgment here. A good game will not get a low(0-2) score due to poor graphics or sound.

For an example.

Arcade volleyball

This classic game was released in 1987 and has now been ported to nearly every system out their. The goal is real simple. hit the ball with your head and hope your opponent misses. Even on my ibm XT the game runs smooth. Worth the download if your into sports games.

Graphics
Sound
Control
Fun
Overall
For cga the graphics are good but the game was released in 1987 so ega could have been used.
Almost none to speak of. Only a few pc-speaker beeps. Nicely timed though and the do fit in so it's not a total loss.
control is fairly good. At times though it can be a bit difficult to get your player to move like you want it to.
It's fun the first few times you play it then the newness wears off.
This is a classic and I felt it deserved a bit higher score than a 2 so I bumped the game to 3.