Questions on rims for experiance ppl >> Need help pls

[S69]

Hi there..

I have a black HB baby, 07, i have some questions on rims

1- What is the best width for 17 inch that will not make any problem on the HB?

2- The same question above but with 18 ?

3- On 18 is there any problem on HB ?

4- The stock rims come with 5.5 width.. what is the max witdh i can put " the car is the 1.3 normal engin " ?

5- The stock rims 15 inch >> any i diea how much they wight ?? with out the tire.

6- What u guys mean by rubbing ??

7- What is the exact use of the strut tower bar and why do we need them ?

8- if 17 inch what is the perfect wight should i get them and 18 inch as well ?

9- If the i get the 17 or 18 > but they are the same diameter of the stock with the tire, and the same wight >> do i still have less power ? ????

10- how do i know the offset size is perfect for my car ?

I would be so thankfull for the experianced answers ...
thanks alot ..