Newb with a few questions

[FJR9]

I really liked Silent Hunter III and some of the mods were awesome!
So I was really looking forward to Silent Hunter 5....Only I've been bitterely dissapointed on how the game runs on my system...

It seems very laggy, takes forever it seems to click on anything, or move my mouse around. I'm not very computer hardware saavy, so I was hoping maybe some of you all could give me a few pointers...

I've read through many posts going back to the game's initial release, and found some stuff that may be helpful...
I tried the antilag download...hasn't helped...I set all in game graphics settings to lowest possible...tried adjusting to a different resolution...no help there....opened up the computer case, and use an external fan to help cool my graphics card...no help there....so I'm kinda frustrated.

the hardware detector tool of SH5 says I meet all requirements....but perhaps not well enough?
my graphics card is an nVidea Geforce G100 with 512mb of ram
my CPU is Intel core duo something or other....
any thoughts on tweaks, or mods etc?
I appreciate the help!