My personal favorites (in no particular order):

GODZILLA, KING OF THE MONSTERS (Simitar). Very good picture quality. Has a weak Godzilla documentary on it.

GODZILLA VS. MOTHRA (Simitar). Good picture quality. 2:35 widescreen. One of the sound options is the AIP GODZILLA VS. THE THING English dub, one of my favorites.

GODZILLA VS. HEDORAH (Sony). Widescreen. Sub-titled. My only gripe would be that they should have included the AIP dubbed feature version.

KING KONG VS. GODZILLA (Universal). Widescreen. Movie looks great and is in widescreen for the first time on dvd.

KING KONG ESCAPES (Universal). Also widescreen. Excellent picture quality. Fun, fun, fun!

VARAN THE UNBELIEVABLE (Toyko Shock). Widescreen and super sharp picture in awesome black and white. This movie is a matter of taste. Lots of fun for some, slow and plodding for others. Only drawback is that it would have been nice to have had the (mostly hated) American dubbed version as a bonus.

GODZILLA: TOKYO S.O.S. (Sony). The sequel to both GODZILLA X MECHAGODZILLA and the original MOTHRA surpasses GxMG by adding Mothra and having Hiroshi Koizumi reprise his role as Dr. Shin'ichi Chujo from MOTHRA.

GODZILLA VS. MEGAGUIRUS (Sony). Fast-paced and lots of fun, this G-film features a foe that can be destroyed by one blast of Godzilla's ray...only she's too fast for him to zap her.

GODZILLA 2000 (Sony). Not the typical Godzilla movie, but with great picture quality and sound, plus a very interesting audio commentary, this is definitely one to pick up.

ALL MONSTERS ATTACK! (Image). Not the best quality, in fact some of it is downright terrible, but this collection of 50 monster movie trailers includes almost ALL of the ones from the Toho Showa movies.

My list of WHERE THE HECK ARE THEY? picks:

MOTHRA
GHIDRAH, THE THREE-HEADED MONSTER
FRANKENSTEIN CONQUERS THE WORLD
WAR OF THE GARGANTUAS
GODZILLA VS. BIOLLANTE

DOCTOR 13