Personaly I do neither. Yet I do no a little about both. First of all cross country is a long corse with many different jumps. There are combinations and logs and water obstacles that you must go over. It is timed and you get faults for refusals. The only way cross country is like endurance is that it is a pretty long distance (yet endurance is longer).
Eventing is when riders come and compete in Dressage, Cross-Country, and Show Jumping. The overal score is counted up from all three events to declare the winner.
Thats basicly all I know (or can think of right now). I hope that helps. Maybe someone else can give you a little more detail.
eventing ~ It is a 3 day event. On one days they do show jumping, on another day dressage, and on the other day cross-country. im not sure of the order witch on is witch for each day. sorry!!!
cross country ~ its like show jumping in a feild. but there is different type of jumps or you go in water and jump over logs while your in the water. Go on google and type in Cross Country. That will help you more!!!