Okay, I've got the art and I've got the maps, what else do I need? Databases are the first thing that pops to mind. I have a spreadsheet I started some time ago with the monster databases for the Savage Fronetier games, so I know that I knew how to get this info.
But, in a spreadsheet is only slightly more useful to be honest. DC has two was that it can import databases - as a txt file or a dat file. The txt file is human readable and easily editable, so I use them the vast majority of the time for my DC use. In the bestest of all worlds, You would be able to write scripts that would take the various databases and and export them to a text file in the DC format.
What would be helpful for me is if it was in a text file that would be serialized so for example we would have "Goblin", next line "10" which might AC, next line "7" which might be the HP, etc.; then repeat for the next monster and the same thing for items.
Oh and a list of the spells avaialable in the game - that is something that I don't have. Any stats would a nice bonus. 
I've made a start on the monster problem (see the attached file). The biggest problem I've got is that I don't understand how the special abilities work in Pool of Radiance's data structures (so I can't translate them into the monsters.txt file) - if Ishad Nha or anyone else has discovered this, please chime in! Anyway, I'll investigate it. There are also some other minor problems, like spells, morale (another byte I haven't found in the Gold Box games) and automatically matching an icon file to the monster, which shouldn't be too hard.
Cleric spells available in pool of radiance are:
Level 1: "Bless", "Curse", "Cure Light Wounds", "Cause Light Wounds", "Detect Magic", "Protection From Evil", "Protection From Good", "Resist Cold"
Level 2: "Find Traps", "Hold Person", "Resist Fire", "Silence 15' Radius", "Slow Poison", "Snake Charm", "Spritual Hammer"
Level 3: "Animate Dead", "Cure Blindness", "Cause Blindness", "Cure Disease", "Cause Disease", "Dispel Magic" ,"Prayer", "Remove Curse", "Bestow Curse"
Level 7: Restoration (found on some scrolls)
Magic User Spells:
Level 1: "Burning Hands", "Charm Person", "Detect Magic", "Enlarge", "Reduce", "Friends", "Magic Missile", "Protection From Evil", "Protection From Good", "Read Magic", "Shield", "Shocking Grasp", "Sleep"
Level 2: "Detect Invisibility", "Invisibility", "Knock", "Mirror Image", "Ray of Enfeeblement", "Stinking Cloud", "Strength"
Level 3: "Blink", "Dispel Magic", "Fireball", "Haste", "Hold Person", "Invisbility 10' Radius", "Lightning Bolt", "Protection From Evil 10' Radius", "Protection From Good 10' Radius", "Protection From Normal Missiles", "Slow"
That is an awesome start for the monster database.

I can see that you are working from an old template, however. We have eliminated "Key" and added a couple of things - see below.
GoldBox/FRUA and DC handle special abilities (SA) very differently so don't worry about figuring out the SA itself - a list of what is affiliated with which monster/item would be all that I need. Perhaps it is similar to FRUA's list of SAs for monstes? These are pretty well documented.
Thank you for the spell list. I am very excited to see that I already have working versions for all of them.

Though, we are using the 1e PHB versions which are hopefully not too different from PoR.
(mostly) blank mosnter record:
\(BEGIN)
name =
icon file = icon_<MonsterName>.png,0,2,48,48,0,1,2
miss sound = sound_Miss.wav
hit sound = sound_Hit.wav
move sound = sound_MonsterMoveStep.wav
death sound = sound_MonsterDeathLarge.wav
intelligence =
armor class =
movement rate =
hit dice =
treat HD as hit points = yes
hit dice bonus =
THAC0 =
magic resistance =
size =
morale =
experience point value =
Special Ability = monsterLevel,
Class = Fighter // fighter is default, can be any class from class database
Race = Monster // monster is default, can be any class from race database
form = large + none
penalty = none
immunity = none
Misc Options = none
item = none
attack =
Undead = none
\(END)
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