Nice, it'll be fun; but to answer your questions, it depends on what you want. A lift is nice for clearance, but if you dont go anywhere where you need that clearance, then you dont NEED a lift. Or if you run taller tires, then you will want to consider a lift.
Wheel spacers are typically used for backspacing a wheel that is very wide. Some wide wheels and tires will rub when turning or flexing, so the spacer helps with those clearances. If you dont run wide tires, you wont need spacers. Or if you do go to wide tires, you could get rims with a different offset to compensate.
The Wrangler was designed with a wider stance in the first place, so rollover should not be much of an issue; but none the less be reasonable in your driving and it wont be a problem.