You could run the risk. I was jailbroken but then I downloaded some tweak in cydia and deleted everything in my iPod. And acted a if it was new and kept on freezing so I took it to fix and I learned my lesson.
You can send me your iPod and I will jailbreak it using the software SN0WBREEZE. First you have to download sn0wbreeze and then download the software for your iPod gen. and then after an hour or so it should of downloaded then you follow the instructions then you wait maybe about 30 min then it'll say for you to back up ur ipod using itunes pressing shift+restore and then you wait about 10 min and ta da u have cydia and then go to cydia, go to sources, press edit, add source, and type in cydia.hackulo.com and then after it loads you press it and then look for installous 4 or 5. Hope this helps.