Cool how you made a description of what you need.
I recommend installing the Huffy codec to capture. It is a lossless codec which is light on resources while capturing. It is pure awesome because there is absolutely no degradation in the captured file as any other codec or format would do.
Huffyuv
Then when capturing is complete, you can encode the file to H.264 codec if you want HD using something like AutoMKV. Then you can upload to Youtube with manageable file sizes and still, very minimal quality loss. If done well, quality loss will be completely unrecognizable to the human eye.
Or you can encode to XviD codec within VirtualDubMod instead which is also very good.