Yep, the option to attach files is there so that you can get feedback off everyone, not just the people who are interested in your chosen programming language.
I ran the file and my first thoughts are that it is quite high resolution, secondly it runs at full frame rate here, however I always have vsync enabled (ppl who swith this of on thier cards bug the shit out of me!) and it is steady at 75 fps which is the default refresh rate of my monitor.
Another thought about it is that it seems to be rendered out of DirectX quads. Speaking as a 100% oldschool programmer who softrenders everything I have never been a fan of DX quads or GL ones either for that matter.
The reason is that these APIs work on a sub pixel level and nearly always have the odd glitch when making oldschool stuff. I can see the scroll working fine but it does have the odd glitch (not because of you, I suspect it's because of the quads).
You may get a smoother result by completely software rendering the scroller and working with it on a pixel by pixel level. As for the frame rate being slow, if it were me making this, if it was running at 800 X 600, I'd be looking to achieve about 170 - 250fps so I think it's in the right ballpark.