Can you find a MiniDV tape head cleaner...
Why dvd?
Probably because it's the most universal video media format available?
Just buy an external(or two) and put all your video there, you can then edit and burn DVDs or Blu Rays(when they come down in price) as needed.
And your PS3 and other devices might be able to play the files direct from the external hard drive.
That doesn't make a lot of sense. Buy an external drive (or two) compared to simply editing now and burning them to DVD? Granted, you can fit quite a bit of footage on even an old 250gb drive (~19 hours), but quality blank DVD's cost less than 50 cents per disc. "File" format on disk certainly makes it a lot harder to give to grandma and grandpa, etc. And as far as putting them on BD, why? You won't gain anything by putting it on a BD, as it's still going to be standard definition footage, burned to BD as MPEG2. You've effectively limited the number of players that can play the disc, however.
PS3's won't play AVI in DV format, due to numerous reasons. It still has to be reencoded to MPEG2, Xvid/Divx, H264, etc.
I'm not trying to be harsh about it, but there is no good reason not to simply just burn them to DVD. Even someone like myself who has HTPC's (running XBMC) connected to every TV in his house, I still burn it to a DVD for an archival copy. Yes, all of my home video's are readily accessibly (as is my entire DVD and BD collection) on 8TB worth of disc on any of the TV's, but again, I still have an archival copy. I've already had bitrot take hold of some things and I won't let it happen again.