Hi Andrew,
If your Samsung DLP set has a native resolution of 720p (most do, unless it's the new Samsung with 1080p), then you should set the DVD player's HDMI output to the same as the set's native resolution. If your DLP set is 1080p, then you could try setting the DVD player to upconvert to 1080i. Your DLP set will then de-interlace the 1080i to its native resolution of 1080p. It may look better than component video connections or it may not.
What sometimes happens is that component-video connections may produce better image quality than an HDMI connection, because the HDMI link uses lots of bits for the anti-copy protection digital "handshake" (and bits devoted to anti-copy protection are bits not used for image quality). Component video connections do not have to deal with complex anti-copy digital handshakes, and hence may look superior to HDMI.
