Is it easy to set up a home server?

[RichardGv]

Huh, it depends. If you want a home server that serves in your home network, it should be relatively easier to set up; If you want, however, a public server in your home, it may not be a good choice:

1. Normal broadband Internet connections usually have an unbalanced bandwidth, i.e. the upload speed is lower than the download speed. However, a normal server requires a higher upload speed.
   
2. It may not be as a stable as a professional server, since no consistent power supply and professional support can be guaranteed. Also, the hardware for a desktop PC is not optimized for the purpose.
   

For detailed instructions about setting up a server with Ubuntu Server Edition, check the official manual: https://help.ubuntu.com/10.04/serverguide/C/index.html.
I'm not really sure about its difficulties. It's certainly pretty difficult if you lack of the knowledge about Linux the system, though. And more knowledge about the server software would be required. Zack, HK, or others that have used a server or VPS may be able to give you a better answer.
Also, Ubuntu is not the best operating system for a server. Debian, CentOS, and FreeBSD are more common choices. Gentoo and Arch may also be usable.