As oromis said, Wii Sports adds are lies. All you do is sit down and flick them wrists. I only got the Wii because I'm a nintendo freak, and so far I've liked it. I suggest, if you want to make it better, when you buy your wii get these things;
Wii Zapper - You'd be surprised how many games actually use it, but don't publicise the ability to use it.
More wiimotes - needs moar
2000+ wii points - get the internet channel, its epic. Also cool wiiware games are defend your castle and world of goo.
WiiSpeak - talk to your mates
Animal Crossing - win
Brawl - win.
No More Heroes - epic win
Like some guy said a while ago, it stays fun if you constantly keep getting news games every month. Most of them are $50-$70 which isnt too bad.
Edit: I also recently got Star Wars Force Unleashed (swinging the lightsabre be cool :D) and battaltion wars (like a TPRTS) and both are epic so far :D