Just do your homework, then try it, you will nvr get good at it if you don't try. We are here if you need any help
for the adb.
download this-
Android SDK | Android Developers
to use andorid sdk you need to have java JDK installed download link here -
Java SE Development Kit 7u2 Downloads
Install the java JDK. first.
After you install the Android sdk open it and click install packages(will take a while to download them)
You will also need to instal the drivers for your phone, found here -
http://www.lg.com/us/products/documents/LGAndroidDriver_WHQL_ML_Ver_1.0_All_Win7.exe
If you have windows 7 . go here C:\Program Files (x86)\Android\android-sdk
The way i get it to work is go to the system tools folder and copy the contents of it, and paste it into the tools folder(I don't if this is the right way to get it to work in W7 , but it works for me)
For ADB shell open up command promt.
type in
cd C:\Program Files (x86)\Android\android-sdk\tools
and hit enter. (if you don't have it open, when ever you need adb shell you need to do this)
On your phone go to settings, then appplication, then in developent make shure USB debugging is check. then plug in you phone to ur computer, and then follow the instructions on how to install xionias recovery.
One you have that installed, flashing roms is very easy. For Kraven cm7 just go to the post for it and it will ahve the install instructions in there.
The first thing you should do after installing xionias recovery is make a nand droid backup. Just turn off ur phone and press the power + volume down + home button at the same time till lg symbol pops up then release, recovery should pop up, then scroll down using the volume keys and selected back up/restore, menu key is enter button, scroll to back up, then let it run. then you ready to flash whatever rom you would like.
Just remember It is alot easier than it looks, Getting the sdk tools installed is the hardest part.
The 2nd hardest part is installing xionias recovery, but its not that hard.
Just make sure to read the instructions and tips on both the xionias recovery post, and the post for the rome, Read it a couple times, and if you follow it you shouldnt have any probs.
Just remember to just come back and ask if you have any problems or questions.
Good luck and let us know how it goes.
Sorry if i was confusing at all