Strange mouse issue

hello,

my wp was up and running ok, until I’ve tried to reduce the number of visible posts in blog pages from 10 to 5 (in total I have 7 posts now so I never had the “previous entry” displayed before).

Now, in my index are displayed only 5 posts and the other 2 are paginated in “previous entries” as it should be, but, the mouse doesn’t work anymore on the content!
I can’t click on links or select text, it’s like I’m on an empty page.
I mean, the pointer is still the same on text, on links, etc. and doesn’t change.

Instead, on the right bar it works, I can click links and so.

I didn’t find anything similar when googled for the problem..
please help me!!!
thanks, andy