It is not a non responsive prompt
Most likely your mongod is up and it is expected behaviour in Windows
You have to open another cmd prompt and connect to mongod
I am trying to understand your requirement
There was no need to stop the mongod which was running as service
This is default mongod which runs on prot 27017
All you have to do is connect by issuing mongo
If you want to start another mongod you have to use different port and path
That is what i meant in my reply
You should not change the default config file
Create your own config file or you can start from command line also
mongod --port xyz --dbpath --logpath
Note:You cannot have two mongods running on same port
Please go through mongo documentation for more details