Is there an equivalent to the Windows Task Manager in AntiX and if so, what's the GUI means to launch it? Is there a keyboard shortcut?

htop.  I think its in the menu.

you can also run it from the"Run" prompts or from the terminal. its actually a terminal app but"mouse aware".

GUI

"mate-system-monitor", installable via synaptic package manager, provides a nice gui.
Upon installation, its launch entry appears in the"System Tools" category of the desktop menu.
For even more convenient access, you could add it as a session autostart item
or create a global keybind (in window manager"keys" file, e.g. ~/icewm/keys)

Compared to winXP task manager, it provides more detailed info regarding each running process and (but) its GUI doesn't"minimize to tray"

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This tiny pyqt4 application (analagous to sysinternals Process Monitor) looks interesting, but I haven't yet tested it.
"procexp -- graphical process explorer for Linux. Shows process information: process tree, TCP IP connections
and graphical performance figures for processes. Aims to mimic Windows procexp from sysinternals, and aims to be more usable than top and ps."

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