I see them as to entirely different genres that have little to no relation to each other.
JRPGs are not RPGs in that the character generally has little choice in determining how the characters interact. So, the player does not take the role of a character, the player is generally the team and battle coordinator with the goal of unlocking more of the story. Levels and skills do not an RPG make. This is not to say it is a lesser genre. It is just different. It has many fans around the world.
WRPGs, again generally, give the player more choices on how the character interacts with others which can change how the NPCs interact with them in return. This is closer to an RPG in that the player does steer some of the personality of the character, within the options provided.
This, of course, all varies from game to game.
I give this thread a 9.5.
The defining feature of a video RPG is it's battle system and all the number crunching that goes with it. If you take out the battle system, you have an adventure game or life sim. Take out character interaction, and with a tabletop derived battle system and plot you can still have a RPG
Video RPGs really do not allow for real role playing. IN a pen and paper game, you can basically try or say anything that comes to mind. For example, if you have a treasure chest in a video game, there are usually only a couple ways you can access the chest. Either you need a key/lockpick/spell or you can break it open. In a real RPG the player can try whatever he/she can imagine. No key? Try dropping the chest out of a window to crack it open. Or haul it back to town to a locksmith. Or take it to a high level mage with an open spell.
But the thing that video RPGs can replicate pretty much to the letter are the battle mechanics of tabletop RPGs (which sprang from tabletop strategic wargaming). The rules, random calculations (the die roll), turns, decisions, etc.