is there a linux equivilant to ctr+alt+del

What about ctr+alt+del?

in windows when a program has crashed or is not responding, you can just hit ctr+alt+del to close the program, is there a linux equivelent to this.

It depends...
Something that always works is killing processes with the command "kill".
To get the ID of the process, use the command "ps".
If you're in a graphic environment "xkill" is really nice, lets you click on the
program window that you want to kill.
I'm running Fedora Core 2 with gnome and the program System monitor
is almost exactly like the window in Windows that pops up if you press ctr-alt-del.

Applications menu
Choose System Tools → System Monitor.

If you've only one instance of an application (or you don't mind killing all the instances) then use "killall appName" then you don't need to know the pid (process ID).

Alternatively, you can use "top" [read the "man top" page], press "k" and it asks which process you want to kill.

pbhj

If you are using KDE, there is an easier way. ctrl+esc is the equivalent to ctrl+alt+del.

ctrl+esc will open the "Process Table" which is very similar to the Windows program manager. It gives a list of running processes and you can kill any one that you are running by clicking on it and selecting "kill". This only works for programs that the user is running. If you need to kill a program that root is running, you will have to do it from the command line. The process table will give you the process identification number (PID). You can kill a program that root is running from the command line with:

kill <PID>

issued as root where <PID> is the number. Just be careful not to kill something important.