Automotive Forums

I saw a previous post addressing bigger rims/tires on a car and how it effects performance and handling. He was mentioning an SUV but I am asking this concerning my 2004 Chrysler Sebring Coupe.

It has stock 17" wheels with tires @ 215/50R17. I am thinking about upgrading to 18" rims possibly at 250/45R18 (excuse me if the first number is off). I previously had a 4-door Chrysler Cirrus and I upgraded the 15" stock wheels to 17" all chrome and my ride was instantly terrible and it wore down on my brakes in the coming years. I am trying to avoid this again my doing some research. My two concerns are:

1.) If I go all chrome again, will it possibly wear down on my brakes again due to the heaviness of the wheel?
2.) Is there a certain tire size I shouldnt go below so it wont completely mess up my ride? (ex. nothing below a tire profile of 45)
3.) What can I do when updagrading to keep or improve the ride quality?

Im thinking of getting an all black wheel with a chrome lip so I can go with the lightweight wheel or the chrome ones which are easier to find. Ive seen my same car with 20" wheels on it. I am wondering if these guys have to upgrade their brakes to handle the difference in weight.  Any advice will be appreciated.