Reanimating Other Species

Most animated skeletons and zombies are either human or close enough to human bodies that there is no significant difference.
However, there may well be situations where a caster wants to animate something else, something definitely not human.
According to the Labyrinth Lord rules for Animate Dead:

"These creatures are unintelligent, and do not retain any abilities they had in life. All skeletons have an AC of 7 and hit dice equal to the creature in life. Zombies have an AC of 8 and the number of hit dice of the living creature +1"

Beyond this I expect the DM/Labyrinth Lord would use his judgement in deciding the rest of the animated creatures' stats.
My guidelines that I would use are:

• I would slow down any movement of zombies by half, to a minimum of 30' per round. Skeletons move at the same speed as they would in life.
• Swimming and burrowing are possible. Flight is possible (but slow and unmanoeuvrable at half speed, minimum 90' per turn) for zombie creatures, but not skeletal ones as feathers for birds or skin for bat-like wings would decay away with the rest of the flesh. 
• Attacks and damage I would keep the same as the living creature, except that zombie creatures always attack last. If fighting PCs with slow weapons that mean they would attack last, the zombies and PCs roll for initiative after the normal-speed creatures have resolved their actions. 
• Saving throws are for fighter levels of half the original creature's hit dice - for unintelligent beasts this may mean no change from when they were alive.
• Morale is always 12 - animated dead are fearless
• As undead creatures, animated skeletons and zombies are immune to sleep, charm, hold and other mind-affecting spells. They are also immune to poison and death magic.  
• Organic poisons deteriorate along with the rest of the creature's body. Only zombie creatures freshly animated can use poison at full effectiveness. After the first day, victims of possible poison attacks gain +1 to their saving throws per day after the creatures death until after 19 days the poison has become completely ineffective. Skeletal creatures don't have the fleshy venom sacs to hold the poison. 
• Although the animated creature is mindless (intelligence 0), its alignment is chaotic, as dark magic infuses its being, giving it an intuitive urge to kill the living. 
• Treasure is irrelevant to these mindless creatures, so they won't have any of their own, though they could be placed as guardians or there may be incidental treasure in their area. 
• Creatures with obvious hard natural armour could retain their armour class, but this is DM judgement call. 
• Creatures with less than 1 HD become 1 HD zombies, or 1/2 HD (1d4 hp) skeletons

Although not explicitly stated in the rules, I think I would restrict Animate Dead to deceased animal things - no animated undead plants, oozes or fungi. As for invertebrates (giant spiders, purple worms, giant beetles, carrion crawlers) I would say that they could be reanimated as zombies, but not skeletons (chitinous exoskeletons decay too quickly to be left after the rest of the flesh has gone, and soft-bodied worms don't even have that). Elemental creatures don't have organic bodies, neither do ethereal creatures.

Here are a few examples from the Hideout of the Gang of Three: (rooms 18 and 26)
Minotaur zombie (AC 8, Move 60' HD 7, THAC0 13, Att 1 horn/1 bite for 1d6/1d6, always attacks last, Ml 12 (fearless), Int 0, XP 440)
Ogre zombie (AC 8, Move 60', HD 5+1, THAC0 14, Att 1 club for 1d10, always attacks last, Ml 12 (fearless), Align Chaotic, Int 0, XP 260 each)
Ogre skeleton (AC 7 Move 90' HD 4, THAC0 16, Att 1 club for 1d10, Ml 12 (fearless) Align chaotic, Int 0, XP 80)

And some commonly encountered species
Giant rat zombie: AC 8, Move 60'/Swim 60', HD 1, THAC0 19, Att 1 bite for 1d4, always attacks last, Ml 12 (fearless), Align Chaotic, Int 0, XP 10
Wolf skeleton: AC 7, Move 180', HD 2+2, THAC0  17, Att 1 bite for 1d6, Ml 12 (fearless), Align Chaotic, Int 0, XP 35
Giant hawk zombie: AC 8, Move 30'/fly 210', HD 4+3, THAC0 15, Att 1 bite for 1d6, Ml 12 (fearless), Align chaotic, Int 0, XP 150
6-headed hydra skeleton: AC 7, Move 60', HD 6, THAC0 14, Att 6 bites for 1d10 each, Ml 12 (fearless), Align chaotic, Int 0, XP 570
Rhagodessa zombie: AC 8, Move 90', HD 5+2, THAC0 14, Att 1 bite for 2d8, Ml 12 (fearless), Align chaotic, Int 0, XP 260
Purple Worm zombie: AC 8, Move 30', HD 16, THAC0 8, Att 1 bite/1 sting for 2d8/1d8, Ml 12 (fearless), align chaotic, Int 0, XP 1500
Centaur Skeleton: AC 7, Move 180', HD 4, THAC0 16, Att 2 hooves/1 weapon for 1d6/1d6/1d6, Ml 12 (fearless), align chaotic, Int 0, XP 80