l have a 2004 buick century with two 12'' subs in the trunk runnin on a 800 watt amp. My radio set up plays dvds as well as cds because of its touch screen, but i've been burning my music via itunes onto dvd-roms recently because it holds more music. Is this bad for the speakers or is it perfectly fine? And does it in fact sound better?

no, theres nothing wrong with playing dvd instead of CDs. l havent burned a real CD since l got my radio that plays DVD MP3 and WMA. all my Cds are in MP3 or DVD so l can have 200 songs on one disk and l havent hade a problem in the last two years. as for the quality, since there is more room on a DVD you can increase the quality settings if you want.