I have a really old ubuntu system. Probably somewhere around 2.0.3 or something. i went to update manager but it wont let me download the new system. I have tried looking online for individual downloads to work my way up to the software but i can't find them. I also have a lot of important things on my computer so i can't "crash it" and "redownload ubuntu" Is there any way to upgrade my system or am i just screwed...?