Gmail’s conversational view is no doubt a very good feature, when you want to see what all conversations took place on a mail. Just in case, if you do not like this feature you may always disable this feature to filter unwanted conversation in a mail. All you need to do is just click on settings which is on the top right hand side of your Gmail inbox and then look for conversational view under the general header.
Now here you will get option of enabling and disabling this feature. So the moment you click on conversation view off, it will take off conversation view from your Gmail inbox. I would still prefer to enabling this feature as it is very important to see conversational view.