basic question for my project

[joerg p]

hello,

I would love to have round about something like this:

A global map, which uses as default background the modis land surface
images. I want to be able to zoom to a specific resolution into this map
and than I would like to use the landsat etm+ images.
So that I can zoom from world resolution (modis) to town resolution
(landsat).......

Is this possible?

Which projection should I use?
Landsat images are in UTM, I tried to reproject them in latlong, but
than the quality is much worse.

What about performance?
I have to tile the modis images. What else?

Should I use WMS Server? Which?


Any suggestions are really welcome,
Joerg