I have a couple of 4 year olds rated 130 would they be good enough for the league and what do i do? i am not very computer literate.

You can't ever really tell until you get them in there. Keep breeding and playing the game. Export them into the race builder and see how they match up to the ones you export later on in your game. If they beat everything on a variety of courses and goings then enter them in the league when it starts up again. Start with a low target in the league, I entered all group races when I started as all of mine were world beaters in the game and got thrashed in the league. But even winning or running well in a small race in the league is satisfying. There are loads of tips on how to get good league horses here and on the league discussion thread if you use the search facility you'll hopefully find lots of helpful threads.

Good luck.