I see the driver I found for you inthis post was only the start of an over-your-head trek to installing a dual-boot Xp & Win 7 system.
You are attempting something that is obviously far beyond your expertise.
The level of difficulty in making your system dual-boot is somewhere between "Advanced" and "Expert." Perhaps you should leave your system as it is unless someone here is willing to guide through the entire process, step-by-step in private messages, or an instant message system such as America Online's "AIM" on a separate computer you might have that can remain connected to the internet during your project.
Consider the level of difficulty in what you are attempting and decide if you are truly up to the task.
If adding a second operating system is not done correctly, you will have no operating system, and thus, no computer.