The Wii doesn't have a built in scaller. It only supports 480i/p or 576i/p (or whatever the PAL resolution is) Your TV scales the image from the input resolution to the display resolution, unlike the PS3 and X360 which try to scale the output resolution to the screen resolution so the TV doesn't have to scale it.

There is no 576p.... the PAL Wii has 3 output options, 576i is the standard PAL resolution, 480i is the NTSC one and 480p is "Extra Definition" which can be a good thing if set up correctly, but not in this case.

buy a upcaler.

I was under the impression it did have one as you could change the res.
I guess thinking about it that's basically PAL and NTSC
That sucks even more. I have mine set to the EDTV one but leaving it to the TV wont yield good results.

I decided to play some of my older GC games on my Wii over the weekend just for kicks and old time's sake, games I haven't played in awhile like Pikmin, Melee, Rogue Leader (which are all launch titles mind you), Metroid Prime, and some F-Zero GX too.

Also, This was the first time I've played any of them on my Wii and subsequently the first time I'm experiencing them on my 50" plasma HDTV, so for the first time I got to take advantage of the 480p progressive scan mode that some of the games offer (my old tv didn't have component inputs so I never got them for my GC).

And all I gotta say is... for games that are going to be as much as 8 years old this fall, they look awesome! F-Zero GX, with its widescreen and progressive scan support, looks phenomenal! Then you go and compare them to the Wii's existing library, and aside from top-tier titles like Brawl, Prime 3, and Galaxy, most of the games in my GC collection put most Wii games to shame visually... it's very depressing honestly.

I swear Rogue Leader will always looks awesome no matter what gen we are in.

What I have been saying in this thread is NOT to use that mode unless you have all the correct cables and your TV has a good upscaler. Use the other outputs and it should have fewer jaggies, although I think it means it doesn't run quite as smooth (but as long as you are happy with how GC games run it doesn't matter)... or I might be getting that mixed up with 50/60Hz option. but either way, turn off the EDTV option.

I'll try it and see.
My Tv has an ok scaler and it's going through component but will see if I notice an improvement.

I hope I do.

Well the wii isn't HD.

I concur with many of the above posts -- if you don't want jaggy Wii games, you have to go with 480i, which is a bit blurry by nature.

I personally don't mind the jaggies... I prefer faster framerate to antialiased images anyday, and I wish devs would allow the antialiasing to be disabled in games where its a framerate hitch... but to each his own.