I saw there was another upscaling thread, but that was focused on HD upscales and rather than derail that one I thought I'd start my own.

I'd like to convert a 4:3 letterboxed DVD to 16:9 anamorphic (all NTSC). That part is simple enough, but I'd like to retain as much quality as possible and I don't mind a slow script, i.e. use various deinterlacing/scaling tricks to avoid jaggies.

Does anyone have any generic scripts that would be handy to start with? I'm pretty new to avisynth, so verbose is good.