Over the years, I've worked through a bunch of issues related to creating video clips. Video clip creation, generally speaking, is a pain in the butt. You don't really choose your input formats and you have to funnel whatever data you get into some output formats.
There are lots of programs that process video. Some are free and some aren't. Nothing "just works" and you can spend a long time wrangling a solution.
This page is series of How-Tos. I separate it by the year I discovered the solution because solutions come and go. I try to do as much as I can with cost-free software that has no spyware.
Disclaimer: I'm not a video expert. I am in the "thank God it works now" catgeory.
As always, if you are in doubt about what you are installing, Sandboxie it.
http://camstudio.org is relatively high quality software. I am able to use it to get about 20fps when recording a 720p stream including OpenGL.
When it comes time to encode the video, you may want to do h.264/AAC which makes it pretty easy to get it into Youtube or Adobe Premier Pro. The best solution to this is to install FFDShow Tryouts, an FFDShow fork that drops a ton of codecs on your system. From there, you can use VirtualDub to get the video into your preferred format.
Out of the box, camstudio encodes video to a Microsoft codec that is pretty lossy.