From what I've gathered you are looking for a way to delete multiple line features at once as opposed to doing one at a time. I may be oversimplifying your inquiry but if this is in fact what you are looking to do it can be done by holding Shift and then selecting the other lines you want to delete. Once you have selected all the lines you want deleted right click one of them and click Delete. This will remove all the lines you have selected at once. Let me know if this isn't what your inquiry was about and I will try to get you the answer you need.
