Its called registry editing if you want to fool around with internet settings. Also you can't modify the tcp/ip stack for windows, as it has to be approved by microsoft in order to function.
The only other thing you could do is get a linux/unix/BSD source code for tcp/ip stacks and see if you can better engineer it for windows enviroment. This will involve API and winsock code, which is microsoft domain. Not to sure if this is available as "shared resource" or not.