Batch file menus. Don't laugh. If you want the user to choose one of three options, you make a simple menu, then make three batch files whose names correspond to the menu choices:
@echo off
echo Please pick a number and hit Enter:
echo 1 - Doom
echo 2 - Duke
echo 3 - Keen
After the above batch file runs, the user is dropped back to a DOS prompt. All you'd have to do is create three more batch files ( 1.bat, 2.bat, and 3.bat ) which would launch the appropriate programs.

If you want to use CHOICE in an somewhat more complicated way, you could have it check for every possible keypress, then accumulate each key in an environment value. This way you could build up an entire word or number a character at a time. The following example shows a limited password-entry example:

@echo off
set userin=
echo Please enter a sequence of letters a, b, or c. Enter q to quit.
:rerun
choice /n /c:abcq > nul
for %%x in (1,2,3,4) do if errorlevel %%x goto add%%x
:add1
set userin=%userin%a
goto rerun
:add2
set userin=%userin%b
goto rerun
:add3
set userin=%userin%c
goto rerun
:add4
echo Your sequence was %userin%

Anyway, if you really want to do it, the code to redefine the Enter key to "Ctrl-z Enter" is [13;26;13p and the code to return Enter to normal is [13;13p. Both these codes must be preceeded by the "escape" character (which doesn't print, so isn't displayed on this web page). An escape character can be generated in Windows Write by holding down the Alt key while typing in 027 using the numeric keypad. You can generate an escape in DOS EDIT by hitting Ctrl-p, then the Esc key. The classic use is to append the con to a line fragment, creating a batch file. Suppose you had a pre-existing line fragment called userfrag.txt containing set userin=

@echo off
echo Enter your name: [13;26;13p
copy userfrag.txt + con temp.bat
echo [13;13p
call temp.bat
del temp.bat
echo Your name is %userin%

Now, the NUL device has nothing in it, so when FC compares NUL to CON, the difference will always be exactly what the user keys into CON. Duh. But FC's /lb option allows us to specify how many different lines will be accepted. With /lb1 specified, FC will quit reading con after the first different line (which will be the first line). All the user has to do is hit "Enter" to define the end of the line.

We also use FC's /n (line numbering) option for two reasons: First, FC puts out quite a few lines. Having it number the lines makes it easy to FIND the line we want. Second, we'll be putting the output of FC into the input of DATE (wonder why?). By numbering the line, we can allow for the otherwise embarrassing problem of having the user enter as a first word something that might be interpreted as a date. The first word will be "1:", which is not a date.

Let me illustrate FC. First, with no options. Notice how I had to enter a Ctrl-z to terminate things. FC's output starts with the line containing "****** CON". My input is the line "this is a test".

C:\Temp>fc con nul
Comparing files CON and nul
this is a test
^Z
****** CON
this is a test
****** nul
******

Next, I'll add in the /LB1 option.

C:\Temp>fc /lb1 con nul
Comparing files CON and nul
this is a test
Resync failed.  Files are too different
****** CON
this is a test
****** nul
******

C:\Temp>fc /lb1 /n con nul
Comparing files CON and nul
this is a test
Resync failed.  Files are too different
****** CON
     1:  this is a test
****** nul
******



C:\Temp>

C:\Temp>fc con nul /lb1 /n | date
this is a test
Current date is Wed 05-14-1997
Enter new date (mm-dd-yy): Comparing files CON and nul

Invalid date
Enter new date (mm-dd-yy): Resync failed.  Files are too different

Invalid date
Enter new date (mm-dd-yy): ****** CON

Invalid date
Enter new date (mm-dd-yy):      1:  this is a test

Invalid date
Enter new date (mm-dd-yy): ****** nul

Invalid date
Enter new date (mm-dd-yy): ******

Invalid date
Enter new date (mm-dd-yy):

C:\Temp>

Enter new date (mm-dd-yy):      1:  this is a test

Now it's time to show the completed example. This only asks for one word:

echo Enter your first name
echo set name=%%5>enter.bat
fc con nul /lb1 /n | date | find " 1: " > temp.bat
call temp.bat
del temp.bat>nul
del enter.bat>nul
echo Your name is %name%.

In this example, because my ENTER.BAT was very simple (set name =%5), I created it by using echo in the second line of the example. Your ENTER.BAT can contain anything you want. If you have a need to process an unknown number of words, just keep using SHIFT to get the next argument. Test each argument after you get it to see if it is blank. If it is, you have no more arguments. Here is an example ENTER.BAT illustrating this:

set name=
:loop
set name=%name% %5
shift
if not "%5"=="" goto loop

Generally, if you write a batch file that expects multiple arguments to be entered by the user on a single line, you're asking for trouble. Think about how much easier it is to get user input and verify it's validity if you do it one step at a time. Nobody enjoys retyping an entire line because one word got messed up the first time. But you'll assume mistakes will never happen.and write multiple-argument code anyway. You can reference %5, %6, %7 (for example) as your first, second, and third arguments. You can go all the way to %9 for your fifth argument. Usually it's enough. If you expect more than five arguments, you'll need to use shift.

fc /lb1 con nul | find /v "*****" | find /v "Resync failed." | find /v "Comparing files" > temp.txt
copy fragment.txt + temp.txt temp.bat

set name=Foo, King of Bar