Move an Image with mouse on the scene?

hi,

What is the fastest way to move an image displayed with "glDrawPixels" on a 2D scene: change RASTERPOS and display again with "glDrawPixels" or translate the scene amoung x and y axis(or another methods if any...). 
Other pb : "glRotate" and "glTranslate" dosn't work on orthographic projection (glOrtho)?

thanks for help!.