Same capture card, 2 different qualies XP Home/ XpMedia

I recently rebuilt my computer and in the process changed from XP Home to Media center and My Avermedia 1500MCE is set up, watching and recording TV but there is a problem. The original software let me choose the codec and different resolutions that let my monitor look closely like the definition of a regular TV and when burning said discs showed no difference on any TV. With media center, its pixilated and the file is about 75% smaller than what I'm used to, I cant install old software, my computer rejects the discs if they have tuner programs on it. I'm sure this has been covered, I just need a nudge or a link in the right direction. Thanks in advance.