I want to put them on a DVD and retain the HD quality
DVDs are standard definition devices.
If you get Roxio's Toast Titanium (with the Blu-ray plugin) you will be able to put about 30 minutes of HD content on a Blu-ray playable disc using your existing burner and media.
For some reason when I insert my DVD to PS3, it does not show up. No matter what, I want to be able to play this on my PS3.
I would think so... What brand and type (+ or -) are you using?
why only 30 minutes worth? Any reason?
Since you aren't using a Blu-ray burner or Blu-ray media, what you are doing is creating a "Blu-ray compatable" disc - not a true Blu-ray disc.