k Nucancer first of all ur normal tv runs at 480i rite, which is standard definition. Component cables allow you to run at 480p or enhanced definition. With normal cables you have composite which is red white and yellow. Yellow is video, white is left channel and red is right channel.
Component cables require you to have a component input. In component cables you have 5 connectors. Basically when you run on 480i (480 interlaced) the info is transmitted alternatively. that is first all the even pixels on your screen will be filled top to bottom on your tv. then on the next cycle the odd pixels will be filled. This happens at 50 hz so your eyes perceive it as simultaneous.
Component cables offer 480p (480 progressive) which means that every line is filled top to bottom consecutively on every cycle. so 1st line, 2nd line.. instead on 2nd line 4th line... To suffice this your cable needs to handle higher rate of data. so what they do is give you 5 cables and 3 of them are colours. i think red blue and green. So higher datarates can be acheived.
From what I've seen on a lcd or plasma you would do well to get component cables and even on flat screens but its not required for a normal CRT. if anything I have heard that the wii looks best on normal tvs with the cables provided.