There are 32 teams in the game. These are the 24 teams that qualified for the USA World Cup plus a further eight that didn't qualify (but that you can play as by using the Customized World Cup Mode). All the teams are listed below together with their ratings. Please note that team ratings in the game are based on three bars for Tackling, Speed and Skill so to convert them to the below numbers (out of 100) I had to take the unscientific measure of a ruler to the screen. Then I averaged out the three derived numbers to get an overall rating for the team. All this means that there may be some human error present in the process but it still should give you an idea of which teams are good in the game and which aren't (Bulgaria, for example, who are rated the worst team in the game despite finishing fourth in the real 1994 World Cup).
Also I have provided information on which group they are part of. Here DNQ stands for did not qualify.
The 32 teams in the game by their rating are: