I have the EXACT same GFX card (82945G) from when I changed my better one when my mother board died and couldn't fit previeous one I had.
PotC didn't play to my computer too, but I used swiftshader and it worked with an awful performance. So I thrown it away and bought CoAS which did not support Intel Onboard GFX cards either... BUT it was playable with a lot better performance than PotC with swiftshader and after some changes like texture quality, sea detail etc., it runs almost perfectly except from the cases of huge battles with 5 or more ships when there is also the solution to NOT turn the camera at the enemy ships.
So, I suggest you trying CoAS - it is worth it anyway.
PotC didn't play to my computer too, but I used swiftshader and it worked with an awful performance. So I thrown it away and bought CoAS which did not support Intel Onboard GFX cards either... BUT it was playable with a lot better performance than PotC with swiftshader and after some changes like texture quality, sea detail etc., it runs almost perfectly except from the cases of huge battles with 5 or more ships when there is also the solution to NOT turn the camera at the enemy ships.
So, I suggest you trying CoAS - it is worth it anyway.