hi! i use powerdirector to convert and edit .avi file to dvd format..when i do my project i have select High quality with total size to save to hdd is 6500mb but when i finish i check dvd folder that i just save file size only 3.58gb, i have try it 2 time but still have same size when i finish..what i did wrong here?

and does subtitle can be turn on or off by remote control when play, as i finish and put disc in dvd to play subtitle alsway display , there is a funtion that you can turn it on or off?

i'm very new to video edit and have no idea what edit software should i use, i see powerdirector ads and have subtitle feature that i want, and i bought it...after using it, i just wonder can subtitle can turn on or off? and multi subtitle languages...
is any video edit software that i can add subtitle and can turn or off? any recommended?