I'd honestly tell you to start with the suspension if you are looking for advice. 18s or 19s on a car with stock suspension can look real goofy. You end up with more wheel gap than tire sidewall, causing a "lifted" look. Do at least a sport drop, 1.25-1.75" to bring the wheel gap down to more acceptable range. It'll make the car handle better and be more fun to drive as well.

As far as wheels go, 18, 19, that's up to you, depends on how much ride quality you want, risk of damage, etc. Pros and cons. Don't get anything wider than 8" and you probably want something in the +42-48 offset range. If the offset is too low, like on a 7.5" wide wheel with a +38 offset, the tire will end up sticking out a bit and you'll rub on the tires under suspension loading.

You probably don't want anything wider than 225. 235 is probably pushing it. Try to keep the overall diameter close to the stock overall diameter when picking the tire width and aspect ratio. Use an online tire calculator if needs be.

Welcome and good luck.