I'm not very knowledgeable with this phone.
I updated the phone, but then it went into CWM-based Recovery screen and it won't let me get to the home screen. I have no idea what to do. Please help.
You have soft bricked your phone. The update will only work if NEITHER CWM or TWRP recoveries are installed. You must be on stock recovery for the update to work, otherwise you end up where you are - soft bricked.
Now you will have to help yourself. Either you are going to have to read and learn how to use LG Flash Tool to re-install a stock ROM, or you are going to have to use ADB to try and undo what you've done - see this post: http://forum.xda-developers.com/show...1&postcount=70
Also, be advised that if you restore your phone and then update while you are unrooted, the new update will prevent you from rooting your phone.