Limiting post on Homepage, not on blog post

Hello, I purchased the Catch theme Pro, and now I'm trying to limit the featured articles on the -home- (page). There are now the same articles you can see then in the "Blog"-section, but I want only 3 articles (the last articles) on the homepage, not more. In Blog there should be more visible. I tried a <?php query_posts($query_string . "&posts_per_page=3"); ?> in the content.php, this works at first, but then the link "older posts" or "previous" on the bottom of the page of 'Home' won't work anymore and I'll get an 404 failure if I click on it ???? I wrote also with your sales manager: (If you need the link of the page where I am already using the template, he got the link within E-Mail from me!) He said, I should limit the blog-post in Settings-->Readings, but that's not what I want. On the section 'blog' there should be more posts visible than on 'Home'. (On home should be 2 or 3 visible, on 'Blog'-page 8 till 10.) Please help! Thank you in anticipation. Jay