[MCL-2507] new user. Minecraft won't launch

very new to computers & games, bought minecraft today for my son. works ok on laptop Win7 (64bit) but won't launch on desktop Win7 (32bit)
The development Console

 Client> Execution protection violation
[18:45:40 INFO]: 
[A fatal error has been detected by the Java Runtime Enviroment 
 Client> #  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x06c67f00, pid=1328, tid=2184

 JRE version: Java(TM) SE Runtime Environment (7.0_55-b14) (build 1.7.0_55-b14)
[18:45:40 INFO]: Client> # Java VM: Java HotSpot(TM) Client VM (24.55-b03 mixed mode, sharing windows-x86 )
Client> # Problematic frame:
Client> # C  0x06c67f00
 Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
 An error report file with more information is saved as:
[18:45:40 INFO]: Client> # C:\Users\colin desktop\AppData\Roaming\.minecraft\hs_err_pid1328.log
http://bugreport.sun.com/bugreport/crash.
 Client> # The crash happened outside the Java Virtual Machine in native code.
Client> # See problematic frame for where to report the bug.
18:45:40 ERROR]: Game ended with bad state (exit code 1)
 Ignoring visibility rule and showing launcher due to a game crash
[18:45:40 INFO]: Deleting C:\Users\colin desktop\AppData\Roaming\.minecraft\versions\1.7.9\1.7.9-natives-24661334154759
[18:45:40 WARN]: Couldn't delete C:\Users\colin desktop\AppData\Roaming\.minecraft\versions\1.7.9\1.7.9-natives-24661334154759 - scheduling for deletion upon