You can download latest version of iOS by connecting your device to your computer and running the iTunes. If asked to upgrade iTunes do it and after that iTunes will update your device ipsw. Please remember to confirm before upgrading that jailbreak for that version of iOS is available or not if you are jailbreaker or willing to jailbreak in future. Otherwise you can safely upgrade your ios version.
We have removed direct download links from this page you can check Apple.com for downloading updated firmware or visit. http://www.felixbruns.de/iPod/firmware/. You can visit our homepage for jailbreak tutorials and guidelines.