This page lists free software that you can use to record your desktop. The frame rate of the recording is not important: 5 fps is completely sufficient, and one can go even further down. The bitrate will typically vary between 50 and 3000 kbps. Please check that text is legible.
Please send questions or comments to email@example.com.
Frame rate: 5 fps
Codec: H.264 (default)
Constant rate factor: 23 (default)
These settings produce an insignificant CPU overhead on my slow laptop. File size: 200-250 MB per hour.