I'm an average home user, but still sometimes use terminal for simple tasks. When I type "terminal" in unity, it offers me three choices - but what`s the difference? I hate always choosing randomly and thinking about what I did.
Terminal is, in Ubuntu default software, the gnome-terminal. XTerm is... https://en.wikipedia.org/wiki/Xterm. UXTerm is XTerm with support to Unicode characters. The main difference between XTerm and Terminal is that the gnome-terminal has more features, while XTerm is minimalistic (though it has features that are't in gnome-terminal, but they are more advanced).
If you are using Ubuntu, you should also have
gnome-terminal installed. For Kubuntu the default terminal is
konsole, and for Lubuntu is
All three are good choices.
To be Desktop Environment independent as much as possible, I would choose
uxterm are good but they use ugly looking fonts, and pose some problems in regards to keystrokes (see How do I set up hotkeys for a xterm?).
Gnome-terminal is generally more of a resource hog than xterm and rxvt. Also, gnome-terminal's install size is generally around ten times larger than xterm's.
By default, urxvt uses a feature called fast scrolling. This causes the
terminal emulator to not always update the window when the content changes. If
a program is outputting a significant amount of data to the terminal emulator,
fast scrolling can result in a noticeable performance boost. Xterm has this
option disabled by default, but you can enable it by putting
True in your
.Xresources file. Gnome-terminal does not seem to have this
Gnome-terminal has profiles that allow you to define and quickly switch between configurations.