xterm in separate consoles 3872
Okay. (But you don't mention just what "low resources" means, leaving anyone who responds to make buttumptions that are almost certain to be wrong.)
Then don't run X at all. You've already got several virtual console, which you can switch between. There is no point at all in starting up X just to emulate what you already have (xterm emuluates a terminal, just as does a virtual console).
I'm not sure with the current implementations of X, but years ago when the average PC was "low on resources", the server took up just about exactly 8Mb of RAM. You needed 16Mb to do anything. You needed 32 Mb to use Emacs without swapping. (To edit images, you needed 200Mb of swap space and a lot of patience... :-)
You can run an xterm without a window manager, but when you call an X app from it, you won't be able to access the xterm while it is running...no...
That's not hard to do, but what it does is start a second instance of the (huge) X server! Perhaps the *last* thing you would want to do on a box with limited memory.
Don't.
Either do without xterm, and use the virtual consoles, or if you really do want to run X apps, start X and any one of the lightweight window managers. Then, rather than have a whole new X server just to get another xterm, you just have one (small) window manager which can provide you with many xterms. And of course, within the limits of whatever RAM you have, you can run any X apps you choose.
If you have at least 16Mb of RAM, run X, and use fvwm2 as a very flexible window manager. You can rewrite all of the fvwm2 menus to suit your needs, and since it uses modules, you needn't load any of the baggage (like task bars and icon bars) you don't need.
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