You gotta strip HDCP. You can do this one of two ways: a special tool that does it for you, or by breaking the bluray out into component video and injecting it into a capture card.
I'd suggest the Blackmagic Intensity Shuttle as a capture card. Plug the capture card into a USB 3 slot on your computer, install the software, change the settings of it in the control panel, and plug into the component video part of it from your blu ray to component video on the capture card. You can then capture the video using the blackmagic card, save it, and export it. I'd suggest capturing it at the resolution and framerate of the video, but do note that the file can get very large with higher resolutions.
And yes, I have to agree, this is a site of thieves and hackers. Everything here is illegal, especially since Jagex has anti-hacking and cheating laws that stand in court (if you get caught hacking, they can justifiably sue your ass for it for manipulating their patent rights). And nothing in the above posts mentions stealing anything, in fact, my reply here is taken from a few customers I've set up to do this. I work with a lot of AV offices and they need ways of capturing segments of video from blurays and DVDs in which they legally own the rights for. Hell, even buying music from Apple or videos from iTunes is still encoded with HDCP, so even if you own the video, good luck watching it on your TV without an Apple TV console.
Do note too, the above capture method also works with video game consoles. You can use it to record your PS3 or Xbox gaming sessions and turn videos out of them professionally.