newer computers come with newer updated programs that your old games can not work with. you will need to update your games, check with the creators & their web sites. depending on the ages of your games & computers you may need to buy new games. if you got thhe games from a place like big fish games they can tell you if thhere is a way for you to get them to work.
The most probable reason as to why the video games might not be playing on your new computer is because they are not compatible with it. You need to check if the video games are compatible and try to see if it is possible to play them. If not, you need to purchase the compatible video games.