Use "I'm talking..." in the following circumstances:
- you want to list examples of something
- you want to express the feeling that there is a lot more than what you're listing
- you're speaking casual English and want to sound rather energetic and emotional
When you list things with this expression, don't use "and". Just keep listing examples, and then when you're done just stop listing things. That makes it sound like there are other items that you could also add to the list, but you're not going to say all of them.
You can just list two examples if you want, or keep listing lots of things. But it's most common to list three items.