It could be helpful if you were a little more specific but...
I think what the assignment is trying to get you to do is understand that the program will not know the data types and the size of the data (row and column wise) until runtime.
From what you're telling me, I would try modeling a table through a mutable list. Program it generically so you can swap out the implementation:
List> table = new ArrayList>();
Is this just video games? If so, I would create a VideoGame object, store fields such as name, maker, system, etc, and put it into a mutable data structureand wallah! It all depends on your operations you will be performing on the list...are you searching and sorting? Do you care about retrieval times?
If you want retrieval to be O(1), or in inaccurate laymen terms, "about one instruction," consider using a Map. If the key is a video game's name, it will return in O(1). If there are multiple entries, consider using a List as the value.
I hope this wasn't too long and confusing but please specify if the number of fields is known or if it has to be entirely generic. If it has to be entirely generic, just use a database! It's made to be generic...or if you really don't want to do that, use the first method I've described.
Hope it helps.