What's wrong with my wii and how can i fix it?

my nintendo wii doesnt work, i've got 3 sensors which only 1 of them sometimes work, which is the wireless one. It works every now and again on the menu, but when i try to go on sims 3, the arrow on the screen dissapears, so i can't click anything. it does it with all the other sensors aswell! i have 2 remotes, one which is a normal one, and one with wii motion plus. i've tried both remotes to see which one works best, and they work the same! i've tried doing the thing where you press the red button on the wii and the remote, but that didnt work either. I payed �40 for sims 3 on wii, and it doesnt work!:( does anyone know how i can fix it, or if not, a cheap way to get it fixed by someone else? i'd prefer not to pay any money though, its much easier and simpler.