I have some experience with gamers that have not played tabletop RPGs, but have played lots of video games including CRPGs. I love the challenge of introducing new players to RPGs. There are some things you need to pay special attention to:
1) You have to be careful to set expectations. Do not promise what you cannot deliver. GMs like to tell new players that their characters can do anything. But in reality, doing anything is alright, as long as it is not disruptive to the other players in the group.
2) Be wary of video gaming tropes. It is too easy to fall into patterns that seem like you’re just making an imaginary video game. For instance don’t: make things impossible for story reasons, create invisible barriers to keep the players on course, killing characters because they do not act in a way you find acceptable or scripting events so that players have no input into the outcome.
3) Finally, be prepared for bizarre activity. At first it will seem like random acts of strangeness. Picking fights with throw away NPCs, trying overly complicated or creative plans to solve problems. What is really happening is the player is testing the limits of what they can and can’t do in this new game medium. They will do this by trying things that video games usually don’t allow. When this happens stop the action and try and explain why what they are doing is a good or bad idea. If you keep these in mind, it will be fun for you to get a new player up to speed and it will be fun for the new player to be able to solve a problem with any approach.