There are some recent threads on this here. The general consensus is if your desire is a professional flying career the least costly is:
1) Attend two year community college
2) While doing 1, train part 61 and get your private, instrument, commercial, multi and CFI
3) Flight instruct while finishing 1 and while you;
4) Attend four-year school school with a useful degree other than aviation (so you have something to fall back on) while you continue to build time. The magic number for the ATP is 1,500 hours which you can get instructing and odd jobs flying (towing banners/gliders, hauling skydivers, pipeline patrol, etc.)
Be sure to acquire some twin time. Easiest way to do that is add your MEI to your CFI. Adding your CFI-I will get you more instructing and IFR time.
Or, drop a load on an aviation University (but pick a real University) which buys you some forgiveness on the 1,500 hours. (see the rules.)