Ah alright then. If your willing to learn a little complex video capture software then check out MSI Afterburner's video capture software. It's part of afterburner so you'll have to install it. If you tune it right, it's the best game capture software I've seen yet. I've recorded 1080P 60fps with it and I can't tell the difference between the video capture and the physical game itself.
You can set the bitrate too so you can choose any file size you want. However, if you want the best video quality but lowest footprint, then I suggest recording in a high file size, then using Any Video Converter to convert it to mp4 and a low file size.