First of all: Welcome to mapster. Great name you got there.
To get your units to explode like banelings you should first get used to the data editor (at least a little). I would recommend the official blizzard tutorial (http://us.battle.net/sc2/en/game/maps-and-mods/tutorials/data/1) to get into it, since the data editor is pretty much the hardest/most complex part of the whole editor.
After that you should take a more thorough look into the data-types units, behaviors (especially the buff type, and in there the damage response field https://www.sc2mapster.com/wiki/galaxy/data/behaviors/buff/), effects (just look at the baneling and all the effects associated with it and try to find/copy the ones that make it explode) and get a first view at actors (especially the events field, just be warned that you will likely be overwhelmed trying to understand this. Just get used to this view and the way everything in this field is ordered into events (when to do something), terms (what conditions have to be present) and messages (what to do) http://wiki.sc2mapster.com/Data/Actors and http://wiki.sc2mapster.com/Data/Actors/Events).
To get other units to explode like the baneling on death, you would first have to create a behavior of type buff, go into the mentioned damage response field, take the effects that you copied from the baneling (see above), get the "uppermost" effect of them (that one that doesnt get called by the other effects but instead only calls others) and put it into the entry Combat - Modification - Death Response - Effect. Then you add this behavior to all the units you want to explode under their field behaviors.
If you want a more throrough explanation on a specific thing (as I only scratched the surface with all that) just ask. If you have gone through everything you still have to apply the visuals (work with actors), but this would be too much to fit in here.
First of all: Welcome to mapster. Great name you got there.
To get your units to explode like banelings you should first get used to the data editor (at least a little). I would recommend the official blizzard tutorial (http://us.battle.net/sc2/en/game/maps-and-mods/tutorials/data/1) to get into it, since the data editor is pretty much the hardest/most complex part of the whole editor.
After that you should take a more thorough look into the data-types units, behaviors (especially the buff type, and in there the damage response field https://www.sc2mapster.com/wiki/galaxy/data/behaviors/buff/), effects (just look at the baneling and all the effects associated with it and try to find/copy the ones that make it explode) and get a first view at actors (especially the events field, just be warned that you will likely be overwhelmed trying to understand this. Just get used to this view and the way everything in this field is ordered into events (when to do something), terms (what conditions have to be present) and messages (what to do) http://wiki.sc2mapster.com/Data/Actors and http://wiki.sc2mapster.com/Data/Actors/Events).
To get other units to explode like the baneling on death, you would first have to create a behavior of type buff, go into the mentioned damage response field, take the effects that you copied from the baneling (see above), get the "uppermost" effect of them (that one that doesnt get called by the other effects but instead only calls others) and put it into the entry Combat - Modification - Death Response - Effect. Then you add this behavior to all the units you want to explode under their field behaviors.
If you want a more throrough explanation on a specific thing (as I only scratched the surface with all that) just ask. If you have gone through everything you still have to apply the visuals (work with actors), but this would be too much to fit in here.