Travelling (spelled traveling in the US) is a verbal noun, so it has a different function in the sentence. It's used (in conversation and writing) to talk about the process of going somewhere. Journey and trip are the same, but because journey sounds more academic, it's much more common to hear people use the word trip in conversations. Travel has the same meaning basically, but if you're going to use it as a noun instead of the verb, you should make it plural and say travels, which is somewhat more academic than trip. So, basically, for conversation, I would stick with trip and for writing, travels or journey.