I should start by saying this is my old personal copy of the game that I bought back in the day. I've heard that GoG fixes incompatibilities before the release games and if putting down the $10 will fix the issue then I'll do it.

My copy of IWD2 runs but not the way its supposed to. When I turn on FRAPS I notice that the game is only doing about 9-15 frames per second when it should be doing 30. I'm running on 64-bit Windows 7 with the compatibility set to XP SP3 and running as administrator. For a game this old I'm not expecting there to be any slowdowns! Can anyone tell me what the issue might be?

I'm asking here because I don't know where else to ask.

Some things to try

In the shortcut properties, disable
- visual themes
- desktop composition
- display scaling

In the game, disable
- 3D
- EAX

Shut down any unnecessary background tasks.

I don't see the setting for "disable 3D" but I did everything else you suggested. It still runs slow, particularly in populated areas. Out in a "wilderness area I can get 30fps but with anyone else on screen it drops. Does it simply not like i5 processors?

Did you run config.exe & set it to high end?
Increasing the AI updates makes them walk faster too.