Text is not aligned perfectly to the grid

Hi Adobe Guru,

I am completely new to Illustrator CS2 and have studied all availabe
tutorial at Adobe and About.com but still cannot solve this problem.

I need to design a Logo with two lines of text of Arial black. The
first line is all cap, bold and 40 pt in size. The second line is all
lower case 20 pt in size. They are in 2 different blue color selection
box. The box is aligned perfectly on the left but the text is not.
The lower case second line text is a few pixel to the left.

How do I justify them so two line to the same width? What I am doing
now is turn off snap to grid, adjust the text size, adjust the
horizontal spacing, the text scaling until they look kind of justify.
I think there must have a easier way to do it, am I right? Is that a
font problem?

Thank you in advance.