does open DSN servers really increase the internet speed..

You mean DNS servers right? DNS servers are servers that redirect you to the correct website. When you go to a website like www.mylot.com, www.mylot.com is actually just a name. What you're really going onto is an IP address which is kinda like a street address for a house. What you do when you access a website is referring to the DNS server for the correct IP and be forwarded there so a DNS server is sort of like the yellow pages book. A lot of internet service providers have their own DNS servers. You can assign your own specific DNS servers (like OpenDNS). The process of this allows you to surf safely and also slightly faster in picking up the address of where you need to go. It in itself won't speed up the actual download process or anything like that but it should pull up pages faster or might not have a single change at all if your provider's DNS server are good.

Yeah DSN servers really increases the internet speed coz when I use to connect my PC with my cell I had to use DSN servers for fast connection.In that case if your phone supports 3G it work far more better.