Unfortunately, I would have to say Robotech. I'll admit that I first saw Robotech when I was young and that was what first got me into Macross. The cool thing was that I watched it so young I actually dont even remember the butchered storyline. I just remembered it was in english and I understood but didnt care whatsoever about the storyline. As long as there were awesome looking planes changing into robots I was jumping for joy.
It was only after Macross Plus that made me intrigue to watch the original Macross again. At the time that I saw Macross Plus, I was in middle school and already Ive figured that most dubbed anime just didnt do justice to what was really being said. So when getting back into Macross, I specifically looked for the Japanese version with subtitles... and boy was I glad to have done that. I didnt even realize how butchered Robotech was until I went back searching for Macross stuff. I was always under the impression that Robotech was ONLY the Macross show brought over to America, renamed and dubbed. Geez... I couldnt have been more wrong.
Basically, getting back to the point... being Asian, I saw my fair share of movies and even anime that I didnt understand... at all. Even tho they seemed cooler to me, for some reason I just couldnt like it as much as the shows that did I understand such as Transformer, TMNT, and Batman. If it hadnt for been for Mac Plus, I dont think I would have ever gone back to watch the original Macross. Just my 2 cents.
Oh... and I would definitely go for anime first... then toy. I remember when I was pretty young and my older brothers were playing with Transformer toys and I didnt think anything of it but years later when I finally saw the cartoon the first thing I did was hop out of my chair and started to dig thru my brothers old toys looking for their Transformer toys.
Plus with toy being after, you can use it as an excuse to give it to them as a birthday gift or something. So when they go, "daddy daddy, I want a cool plane like that *points at Macross on tv*", you can just respond with, "oh, really?... I'll buy you one for your birthday cuz I'm a cool dad."