Downloading the IPOD programme upgrades

First: I'm not that techno savy so please bear with me..

I have a two year old IPOD.
Over the two years i did not upgrade the various versions of the working/downloading programme on the IPOD when i logged into the music sites.
Now i want to download some music that it requires me to download the upgraded versions of the programme from scratch (I think) to allow me to download the music I want from the site...

Question: I have over 200 songs on the IPOD. If I download this programme all over again, do i loose the music I currently have? If not how do i get this music back onto the IPOD if it is linked to the old programme version????????

Please help !

How do you get music onto the iPod? Do you use Apple's iTunes software? or something else?

I use ITUNES !

OK - So all your music should be in iTunes so. Can you play these songs on your PC using iTunes?

If so, you'll have no problem when you upgrade your iPod, as iTunes will send the songs back down to your iPod once the update has finished.

I don't quite understand the ' Now i want to download some music that it requires me to download the upgraded versions of the programme from scratch (I think)'. Are you sure that this isn't some dodgy filesharing site that is loading dodgy software onto your PC?