Part One -
The Vision's first appearance in comics was in Avengers #57 (1968), and was created by Roy Thomas and John Buscema. Ultron, a robot created by Hank Pym (better known as either Ant-Man or Giant-Man), who went rogue and fought the Avengers on several occasions, created an android himself, which he called a synthezoid to fight and destroy Pym and the other super heroes. Intended to be the "perfect vision of the future", the android adopts the name Vision and soon learns that Ultron used the brain patterns of then-deceased Wonder Man as a template to create him. During a fight with the Avengers he is convinced to rebel against his creator, and eventually joins the super hero team and forms a relationship with fellow team-mate the Scarlet Witch.
The second season of the Fantastic Four animated series that aired in the mid-90s on Fox Kids features cameos of the Vision in a couple of episodes. This second season was a vast improvement over the disappointing first season. Vision appears as a member of the Avengers, although he doesn't have any lines, his name is never mentioned and he is usually on-screen for less than a minute. He can be seen in the episode "To Battle the Living Planet", where he helps the other Avengers save some people from a car trapped under a collapsed bridge. He's later seen in the final episode, entitled "Doomsday" once again alongside the other Avengers fighting the super-powered Doctor Doom. Doom managed to obtain the Power Cosmic from the Silver Surfer, something he already did on the show once before, if we count the first season finale, but I liked the way this episode handled the story better anyway. Co-incidentally, his cameos take place in the same two episodes where we get to see Hercules - another Marvel comics character I have started a retrospective about.
Vision was a main character on the Avengers: United they Stand animated series which started airing in the late 90s also on Fox Kids. The show lasted for only 13 episodes; it didn't feature any of the more well-known Avengers as regular characters (although Iron Man and Captain America did guest-star each in one episode), and the heroes had some silly armors they had to wear during their missions - as well as various models, such as jungle armor. The Vision was spared from such an armor, I'm guessing because he was already made out of metal. Overall, the show was pretty bad and none of the characters ever did anything that interesting, making the show very boring and forgettable. I never really liked any of the characters featured on this show, though to be fair I was never a big fan of either Ant-Man, Wasp, Hawkeye or any of the others, at least until Avengers: Earth's Mightiest Heroes premiered. Pretty much every character on this show was presented far better than on United They Stand. Hank Pym (as both Ant-Man and Giant-Man), Wasp and Hawkeye are all awesome on Earth's Mightiest Heroes and make the previous Avengers show even more forgettable. And while Vision and Falcon have appeared very little so far, I think it's safe to say they will also fair better than in their previous animated appearances. But I'll get to Earth's Mightiest Heroes in due time, and I'm pretty sure I'll have nothing but good things to say about it. But until then...
Since Vision was featured in every episode of Avengers: United they Stand, I'll just comment on his most notable appearances on the show. Here he was voiced by Ron Rubin, and as in the comics, he is introduced as the newest creation of the evil robot Ultron. He first appears in the series premiere, the two-part episode titled "Avengers Assemble", where Ultron sends him to attack the Avengers. As a side note, I find it interesting that this same title would later be used for the series finale of Earth's Mightiest Heroes, and as the title for a new Avengers animated series, which hasn't even premiered yet; I'm not trying to say these series are in set in the same Universe or that they shouldn't have used this title (it is a pretty common phrase in the Avengers comics), I just found it interesting.
During Vision's attack on the Avengers Mansion, Wonder Man (Simon Williams) is injured badly. Trying to save his life, Ant-Man comes up with the idea to transfer Simon's memories into the android's body, who they managed to de-activate earlier. Despite Scarlet Witch's protests - she apparently was in a relationship with Simon; I guess, since the show didn't really explain it that well - the transfer is done and now the Vision is re-activated. Now having a conscience the android turns against his creator Ultron and is allowed to join the Avengers. Like I said he never got an armor on this show, but he got a belt buckle with the Avengers' logo on it. But Ultron manages to steal Wonder Man's comatose body from the Mansion, which leads to some sort of story-arc for the series; the Avengers have to save him from Ultron.
In the episode "What A Vision Has To Do", the Avengers manage to rescue Simon from Ultron. Here, the Vision volunteers to act as bait for Ultron, part of an elaborate plan. I thought the idea was pretty good, but executed badly. Vision pretends to go rogue, in an attempt to trick Ultron into believing he has returned to his original programming. Ultron then comes to retrieve his android, and the Avengers track Vision back to Ultron's base where they do manage to save Wonder Man and take him back to their Mansion. But the story-arc is still not over (and unfortunately won't end by the time the show finishes its run) since they still don't have a clue how to wake him up from his coma.
Towards the end of the episode "The Sorceress's Apprentice", Wanda the Scarlet Witch manages to bring Simon back to life by using magic. And so Wanda is reunited with her beloved Simon. The episode seems to imply Vision is actually jealous, and there were a couple of hints about a possible romance between him and Wanda but since none of the characters were developed enough to make it clear. Simon's brother, the villainous Grim Reaper also appears in this episode but nothing apart from him being Simon's brother is actually revealed about him. Considering he only appeared in this one episode and near the end of the series, they could have explained a little more.
The series finale, the two part episode "Earth and Fire", features the Avengers fighting the Zodiac, a group of alien super villains who have had cameos in two previous episodes, but their origins or motivations weren't really explained. Apart from their leader Taurus who gets a decent amount of screen-time (but not even that makes him an interesting enough character) most of the other members don't even get to speak. This two-parter has some long, drawn-out and uninteresting fight scenes between the Avengers and the Zodiac, which make it pretty boring. Most if not all of the story lines spread throughout the 13 episodes of this show don't get any proper resolution and end on cliff-hangers, including the Vision - Scarlet Witch - Wonder Man story. Overall, the entire show was pretty much a mess and I personally wouldn't recommend it to anyone who hasn't seen it before.