Problems w/ Page Layout Using Thesis Theme

Can anyone help with this problem

I made changes to my home page and my subsequent pages also changed

my opt in form is very long and big

my paragraphs and no longer formatted the text on the page has lots of spaces etc and the font size has changed

I know it is something to do with using the thesis template which is overriding the css code but I don’t know what to do

My blog now look terrible

Please help