In your httpd.conf file of apache directory listing is on. so when no .html page in directory you are viewing then it will browse the files or dirctory contains in that directory. when you place index.html or index.htm in that folder then after you will not get directory listing.
so place index.htm or index.html in /var/www/html/squid directory after that you will not find directory listing.
If you want to redirect then you can place code in index.html file.
and for your other problem :
192.168.1.2:80 -> redirects to another computer
if no code in default page of apache then this may be done by firewall.