Problem Server .bat file help.

[TitanArmadillo]

Intel Core i7-2600K 3.4GHz Quad Core
8 Gigs of Ram
Nvidia Geforce EVGA 770
Windows 7 Ultimate 64 bit
Java 8 Update 25 (64bit)
Java 7 Update 71 (64bit)
FTB Monster 1.1.1 for minecraft 1.6.4
No changes in Edit Mod Pack, No changes to any files except .bat file.
Im trying to host ftb monster server on my pc but my .bat file defaults to using java 8 which yields this error.

2014-12-21 11:10:53 [SEVERE] [ForgeModLoader] Unable to launch
java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
at java.util.ArrayList$Itr.remove(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:114)
at net.minecraft.launchwrapper.Launch.main(Launch.java:27)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at cpw.mods.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.j
ava:48)
at cpw.mods.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.
java:17)

So I tried to fix this by modifying my .bat file from:

java -Xms2048m -Xmx2048m -XXermSize=128m -jar FTBServer-1.6.4-965.jar nogui
pause

To:

"C:\Program Files\Java\jre7\bin\javaw.exe" -Xms2048m -Xmx2048m -XXermSize=128m -jar FTBServer-1.6.4-965.jar nogui
pause

When running this .bat file a normal windows command prompt popped up like normal, but unlike normal it didnt display any of the server startup processes, errors or messages. It just showed me the text in the .bat file. But I know the server was actually running because in my server folder logs and files started appearing.
So I tried to fix this by removing the nogui in the .bat and launching.

This time the normal white minecraft server window appeared and displayed a few messages but not even close to the ordinary amount. And it also failed to bind to port, this lead me to check the active processes and there was 3 javaw.exe (1 client 2 servers) which means that closing down the command window for the nogui server didnt kill the server.

I killed all 3 of the javaw.exe processes, relaunched the server without the nogui and it seemed to be working, no failure in binding to port this time but still not the normal messages. So I came here in hope of finding a solution that will let me run the server with the ordinary nogui and see all the server messages.

 

[TitanArmadillo]

While direct google searches didnt yield any results after some browsing I manged to find that it was my choice of javaw.exe instead of java.exe which stopped the usual flood of messges in the nogui server. While this fixes my problem I would still appreciate some advice on what values to put after -Xms and -Xmx considering I have 8 gigs of ram.