There is a way to install ubuntu 9.1 on the n900. This is a "normal linux" and "nearer" on linux than easy debian. Linux IS a server os AND a Desktop OS. It makes no sense to differ this. With a apt-get install apache2 you will habe a Apache Web-Server, with apt-get install xyz you can install some server services you want. But you then have to configure this services. To learn linux, the n900 is a smart way.