I know that I can get Unix on my Ubuntu 11.04 but I was wondering what I need to do to change it from a Linux to a Unix.
Plus I have all of these programs on my HDD and been looking online to find out how to get rid of the ones that I no longer need or use.
Not sure I understand correctly.
Ubuntu is a series of distributions BASED on linux kernels - HOW do you "get Unix on my Ubuntu 11.04"?
HOW do you determine "programs ... that I no longer need or use"? You may not have run a command for a long time, or even never, but still it is / they are vital to the innermost system.