Zolgar: D&D 2E rules suck for video games. Actually no wait, D&D rules suck for video games, period. D&D is NOT meant to be a video game. In Planescape they realized this and VASTLY modified the system.
Hawk52: Can't say I agree with that. The Baldur's Gate/Icewind Dale games work very well for what they were attempting to do., And Temple of Elemental Evil has some of the best turn based combat I've ever seen in an RPG. It's just everything
else about the game is pretty broken.
IWD, ToEE and Bg kinda.. make it work.. but it's still anything but ideal.
One thing to consider is I am a D&D nerd. I know 3e/3.5 in an out, and I know enough about 2E to understand it's mechanics.
D&D mechanics are built for a couple of fights a day, each one with only a few foes (until late game at least), it's built for spellcasters to consider their options as to whether or not it's a good idea to use their best spells in a fight, because they might need them later. Even the toughest heroes don't have all that many HP compared to weapon damage at low levels. And let's not forget the slow leveling speed of D&D.
In a tabletop game, these mechanics work.. usually. In a video game, they don't work as well, especially not combat driven ones. ToEE: very combat driven. IWD: pretty combat driven. BG: I dunno, seemed fairly combat driven to me.
In a tabletop game, you might fight 2 groups of 4 foes in a day, with a party of 4. In video games you'll get that in 5 minutes. This leads to, especially if you have mages, needing to pretty much sleep every 5 minutes, which is really dang annoying. Also the number of foes you get hit with, even at really low levels, can with just a few lucky shots tear your melee fighters to pieces.
And because the number of foes is so greatly increased, in most video games, they cut the XP earned down to a bare fraction of what it would be in the tabletop game.
It -works-, but it doesn't work WELL. The system they use is handicapped from the get-go for video games. A few tweaks to the system, and you'd have a fairly nice setup for a tactical combat game. Vanilla though, it's pretty weak.
For a D&D based video game in 2 or 3E, what they would be best off doing:
Initial HP boost, and slight boost to HP/level. (start with 20+max HD, get max HD every level)
'Mana' variant for spell casting, with the mana recovering on it's own.
Slight buff for stats. (something akin to a higher point buy, or a couple of passive +Xs that you could distribute once you had your stats.)
This would not really change any of the core mechanics of the game, but would make them much more suited for a combat heavy video game.