I Cant Start My Server?

If you are running a 32-bit the maximum you can do is 1024M so, for your run.bat you will need to do the following:

java Xmx1024M -jar craftbukkit.jar -o false
PAUSE

Also be sure to rename your jar to match the "craftbukkit.jar" part, this can be called whatever, as long as it matches up.

What you need to do is put a file named MineCraft server on your desktop. Then you need to get the .jar file/bukkitt.jar. After you have the jar file put that in the folder. If that jar is called craftbukkit-1.6.4-R2.0 or something other than craftbukkit, remove it. The jar needs to be just craftbukkit.. Then you make a new text doc. You will paste this code.
java -Xmx1024M -jar craftbukkit.jar -o true
PAUSE

After you paste the code save the text doc as start.bat. You should be able to run the server and then its just a matter of port forwarding.

I have 8G of ram

How many gigs of ram do you have, maybe your computer can't handle a server. And update Java just to be sure.