As I'm bored at work..
A - All are from Space Crusade.
B 1 & 2 - The bright colour back packs are from Space Crusade.
B 3 & 4 - 3rd edition 40k Space Marine backpacks
B 5, 6, 7 - 1st/2nd edition 40k Space Marine backpacks
C 1 - RTB01 Space Marine Bolt Pistols
C 2 - RTB01 Space Marine Boltguns. The other bits, the bayonets, fit on the end of the Boltguns
C 3 - RTB01 Space Marine Missle Launcher missles
C 4 - RTB01 Space Marine Ammo clips/pouches
C 5 - RTB01 Space Marine Knives
D 1 - RTB01 Space Marine Power Fists
D 2 - RTB01 Space Marine Boltguns
D 3 & 4 - RTB01 Space Marine Bolt Pistols
D 5 - RTB01 Space Marine Missile Launcher arms
D 7 - I did a similar conversion.

D 8 - RTB01 Space Marine arms
D 9 - You've got a mixture of 2nd edition Ork, Imperial guard, Genestealer Hybrid arms. All of these are quite collectible on ebay.
D 10 - The dark blue heads are RTB01 Space Marine sergeant heads, I can't accurately make out what the grey ones are from the photo but they could be 3rd edition 40k Dark Eldar heads?
D 11 - RTB01 Space Marine Heads.
E 1 - 40k 2nd edition/Space Hulk 1st edition Genestealer Hybrid Conversion Beamer
E 2, 3, 5 - 40k 2nd edition Heavy Bolter. The ones with arms attached are Space Marine Scout Heavy Bolters.
E 4 - 40k 2nd edition/Space Hulk 1st edition Genestealer Hybrid Missile Launcher
E 6 - 40k Vehicle pintle mounted Storm Bolter
E 7 - 40k 2nd edition/Space Hulk 1st edition Ork/Genestealer Hybrid bolt guns
E 8 - 40k 2nd edition/Space Hulk 1st edition Ork/Genestealer Hybrid bolt pistols
E 9 - 40k Rogue Trader Imperial Guard/Squat lasguns (these are quite common, I've got bucketloads of the things as they're not worth the effort to sell them)
E 10, 11, 12 - Not 100% sure but they could be Space Crusade Dreadnaught heavy weapons?
E 13 - 40k 3rd edition Space Marine knives
E 14 - Possibly 40k Imperial guard knives?
E 15 - Looks like a 40k Chainsword
F 1 - 40k 2nd edition Tyranid Boneswords + Tyranid armoured chest plates + Tyranid claws
F 2 - A bad condition 40k 2nd edition/Space Hulk 1st edition Chaos/Genestealer Hybrid Autocannon
F 3 - 40k 2nd edition Imperial Guard/Ork Heavy Bolter
F 4 - 40k 2nd edition/Space Hulk 1st edition Ork/Genestealer Hybrid Chainsword
F 5 - No idea
F 6 - 40k 2nd edition/Space Hulk 1st edition Ork/Genestealer Hybrid Plasma Gun
F 7 & 8 - Not sure, could be Space Crusade weapons.
F 9 - No idea
F 10 - This is the ammo pack for F 1 and a 40k 3rd edition Dark Eldar helmet.
G 1 - Chaos Androids from Space Crusade
G 2 - Space Marine Librarians from the Space Hulk 1st edition Genestealer expansion
G 3 - Genestealer Hybrids from the Space Hulk 1st edition Genestealer expansion
G 4 - 40k 2nd edition Tyranid Death Spitters (I think that's what they're called)
H 1 - Space Crusade Gretchin
H 2 - The ones on the round base are Space Crusade Orks. The one of the rectangular base is a Heroquest Orc
I - The top model looks like parts of an incomplete Chaos Dreadnaught from Space Crusade
I - The plastic bits in the container look like bits from Warhammer Empire troops.
I - The Jerry cans could be from anything.
I - The lights are 40k 2nd edition Imperial Guard Vehicle lights.
I - To the right of those are 40k 1st/2nd edition Rhino hatches