poor quality after exporting to qt and burning in idvd

Hi.

I am a wedding videographer and have been shooting with my Sony Z!J in dvccm up to now and i have not been happy with the final quality of the dvd i give to my clients, so i decided to take the plunge and change to HD.

I capture my footage from my Sony Z1J HDV in 1080i50i in to Final Cut Express HD and create lovely movies with lots of music, transitions, titles etc and it looks great in the little window in FCE.

I then export my project using quick time movie (tried both self contained and not self contained) and looks a little grainy and blurry when i play it back on my mac, however, when i drag it in to idvd for burning on a dvd, it looks very poor indeed when playing back through a dvd player to watch on tv.

Have i got any settings wrong? or does anyone have any ideas.

I am getting very frustrated and am wondering if i should change my camera to sony x70 and FCE to Final Cut Pro x???

Thank you

David