Windows 7: Games play better because?

I have Quake 4 I play on Vista with a SATA2 750 Seagate HD which has a 16 MB buffer and I put it on high resolution for lack of a better word and the mouse was sluggish. I put Quake 4 on a SATA2 1TB Seagate HD which has a 32 MB buffer and put it on high resolution and the mouse is as smooth as silk. Is it because of my better hard drive, Windows 7, or the 64 bit OS that Windows 7 is on. I think it's because of Windows 7 period and my better HD might have a 10% enhancement but is the 64 bit OS helping any because this is a 32 bit program. This is the same computer. Any ideas why my game is running so smooth?

You did not specify any difference in mouse settings.

Assuming they are the same, you are benefitting from enhancements in the new OS. HDD buffers are not affecting the mouse.

They are the same as with everything else in the setting. If I take a new program and put it in a old computer and the mouse is sluggish wouldn't that be from lack of power on the computers part such as CPU, RAM, Video Card, and Buffering?

Is it the same mouse?

I have never had a "sluggish" mouse whose performance had anything to do with the mouse itself. Usually indicative of a pegged out CPU. For me, the most common cause of a pegged out (running at 100%) CPU are configuration errors or buggy apps, or even MS.NET doing it's initialization thing.

A specific example is required to provide a proper answer.