DVR Chatter

I'm a new user.  I'm cheap.  I only have off-air HD...no cable or satellite.  i'm not a huge TV watcher so i just want to record something on rare occasion. in a way that doesnt require any subscription.  I would like to recorder to replace my old VHS system.  I recognize i cant record true HD with anything, but what will give me good pic quality (with upconvert?)?  is a DVD the only record format or are there some hard drive units compatible with free off-air HDTV?  if i leave the recordable DVD in the same unit all the time, what format should i buy and use, and how many re-uses can i expect?  if i'd like to record and move the recording for one-time viewing on another DVD player, do i have to "finalize" the DVD and it will not be re-recordable after that?  i really like panasonic but read lots of horrible reviews about the DMRE27K and its propensity to "freeze" or screw up recordings...any advice there?  And i would like to watch one program while recording another, or record with my 50" Sony Wega 1080i off, so this unit needs a good ATSC tuner I presume.  So in a nutshell, what DVD recorder should i buy??  thanks!