I will try and provide brief impressions to the games I own or have played (for more than an hour). Just as a reference, I don't mind mini-game collections if they're good; if I say something like Mario and Sonic at the Olympic games is bad, it means it even fails at being a being a shallow momentary distraction.
Mario Strikers Charged: Fun arcade soccer game. Great multiplayer, think it has online too.
Pro Evo Soccer 2008: Different kind of soccer game based around the pointers. Good game.
Marble Saga Kororinpa (2nd one): The best Marble Madness/Monkey Ball style game on the Wii.
House of the Dead Overkill: Great light/rail gun shooter mix, and while I didn't care for the wannabe grind house cutscenes, others liked it.
House of the Dead 2&3: It's house of the dead 2 and 3...yeah. If you have a Lightgun shell like Nyko's Perfect Shot, this has a calibration tool to make it control "right"
Ghost Squad: Ditto to everything with HOTD2&3.
Resident Evil Umbrella Chronicles: Similar to HOTD Overkill but total garbage. Pass on it.
MLB Power Pros: It's a japanese baseball game. Easiest way to describe it would be to say it is like RBI Baseball on the NES.
Nights 2: Haven't played much but seems enjoyable. Original Nights was great and this didn't seem as good, but I still want to go back to it.
Links Crossbow Training: It's like $2 and is a fun target shooter, rail shooter, lightgun shooter, third person shooter based around assets from Twilight Princess.
Warioware Smooth Moves: It's Warioware where the gimmick is now a bunch of waggle games. It's fun.
Boom Blox: haven't played the sequel, but the first one is a really fun puzzle game. It's about chain reactions and physics and stuff, kinda like Burnout Crash mode.
NSMB Wii: Awesome. It's a bit easy, the music and general style is lacking whimsy, and some levels resort to waggle dipshittery, but it's a 2D mario with great single and multiplayer.
Mario Party 8: Garbage
Mario and Sonic Olympic Games: Ultra Garbage
Dead Space Extraction: Got bored after an hour. Seems as much about having you watch cutscenes in first person than being a lightgun/railgun shooter. Looks great, at least.
Red Steel: Broken FPS/waggle slash game set in racist modern Japan. Still, uh, if you enjoy bad games that still provide some entertainment, this is one.
Red Steel 2: Only played about an hour and it seems fun. Lacked the impact of a first person brawler and felt more like shallow Devil May Cry in first person. Will buy it eventually.
Sin and Punishment 2: Only played a bit but it was pretty awesome. Runs smooth and has great pointer controls with no waggle shit.
Silent Hill Shattered Memories: More Heavy Rain or Myst than Silent Hill. Walk around environments, solve neat puzzles, and occasionally deal with terrible chases. I liked it.
Punch-Out: It's Punch Out 1 on NES. That's pretty much it. If you played Punch Out on NES, you have played this.
Final Fantasy CC Crystal Bearers: Tiesto's impressions are spot on. Shallow lighthearted entertainment. I enjoyed it.
Excite Truck: Feels like off road burnout. As much about earning stars from driving than it is about placing. Really fun racing game.
ExciteBots: Trash. Takes Excite Truck concept and turns it into doing stupid mini-games on a loop.
No More Heroes: Shallow action game. It has style and that makes it entertaining, especially the boss fights, and after NMH2 I appreciated this game more.
No More Heroes 2: Trash. Bad action game with no personality. If you enjoyed the first game at all, I dunno, but NMH2 feels like a giant waste of time.
Metroid Prime 3 (or Trilogy): Really, if you played Metroid Prime 1 or 2, you know that MP3 is already. Big change are the controls, which are great pointer controls now.
Wii Sports Resort: Ping pong, bowling, golf and sword fighting are awesome. The rest are boring.
Wii Sports: Like WSR, but older and worse. Best parts from WS are recreated in WSR.
Mario Kart Wii: I think it is one of the weakest Mario Kart games, but still entertaining. Feels very slow and requires less skill than older games. Fairly sterile look, too.
Zack and Wiki: It's a puzzle game made up of puzzles you'd find in an adventure game. I think it's great despite the occasional control issues.
Wario Land Shake It: Really super easy 2D platformer that is most worth it for how nice it looks, especially in motion (more than Muramasa and Odin Sphere)
Little Kings Story: Awesome game. Mix of Pikmin, city builder, and shooter with whimsy out the ass. Best Wii game of last year.
Resident Evil 4 Wii: Best and most complete version of RE4. Worth buying it again.
MadWorld: I liked someone else's description of an inferior Dead Rising. You use environment on enemies to build points to unlock boss fight. It's fun, not great.
Gundam Sensen (import): It's an FPS Gundam game with a squad, customization, and a lot of missions to take on. Great but it is an import, so no english.
Tatsunoko vs Capcom (import): Haven't played the US verison but the import is basically a shallower version of MvC.
Disaster Day of Crisis (import): Entire game is a Michael Bay wankfest. The story is basically The Rock. The game itself is a bad lightgun game mixed with waggle mini-games.
Tenchu 4 Shadow Assassins: Awesome. Action/puzzle stealth with wonky Wii controls. If you have a PSP, get that version instead.
Sonic and Secret Rings: Not good. It's one of those games where people claim it's "sonic in 3D done right" because you run really fast, but it's just boring.
Elebits: Fun game where you have a gravity gun and throw chair and shit around a room to find little creatures.
Batallion Wars 2: Barely played this because I found it boring. Seems like third person squad based shooter or something.
Castlevania Judgement: Shallow by arena fighter standards with neat Castlevania fanservice. Not worth it.
We Love Golf: Trash. Controls don't work.
Super Swing Golf Pangya: Like Hot Shots/Mario Golf with worse controls. Actually, if you get a Golf game, get Tiger Woods that supports Motion plus.
SSX Blur: Not good. If it didn't have terrible controls it would be interesting, but it does!
Super Paper Mario: Boring mario action rpg that is SO BORING
Klonoa: It's a Klonoa 1 remake. Awesome if you haven't played it before, still awesome if you are playing it again.
The Conduit: Trashy first person shooter on Wii. If you own any other system, there are far better FPS games to play.
Wii Music: Trash. You waggle to free midi music and shit like that. Insulting by baby toy standards.
Victorious Boxers Revolution: aka Hajime no Ippo boxing game that isn't as good as the PS2 games.
DBZ Budokai Tenkaichi 3: fun Dragon Ball Z fighting game with pretty much every character from DB, DBZ, and DBGT.
Samba De Amigo: It's Samba De Amigo if the controls didn't work.
Super Monkey Ball Banana Blitz: Trash. Get Kororinpa.
oh, and Wiiware:
Bit.Trip Beat: entertaining pong based rhythm game
Art Style Orbital or w/e they call it: Great game based around gravity and planet orbits.
Castlevania: It's a pre-SOTN Castlevania game and it's pretty awesome.
Lost Winds: Short but entertaining.
Cave Story: If it's like Cave Story on PC, it's awesome. Metroid style game.
I'm forgetting a few games. I sold a lot of my Wii games and since most were so boring I forgot about them. But one I just saw on my shelf was Smash Bros Brawl; that game is pretty fun. Single player is a weak platformer/action game and multiplayer feels like a dumbed down Melee. Still worth it if you enjoyed Melee.