Home key?Screen Lock stopped working this morning

Hi all, new to the forum because until this morning, my LG Optimus V had been running just fine (for the most part) lately I have been having errors that my phone was low on storage, so i cleared the memory in all my apps, without reading about it first. Now this morning, my phone seems to be a hot mess, the home button has stopped working, my screen lock wont come on (even though i have it turned on in the settings). I am not super computer or smart phone savy, but if some one can walk me through how to fix this, i would really appreciate it!!! Thank you!!

Hello and welcome to the OV forum(s) :)
I am not going to write a book to you as to what happened...there are pretty easily found stickies on these issues and also the home button issue.
The internal memory on our phones is indeed small. Installing a custom recovery and ROM is definately required if you are constantly running into this issue. It is called sd-ext. Basicly can move and link apps onto your SD card. You should buy a new larger one if your still on stock 2G.
But before all this comes rooting.
Take a day or two and read up the threads. It pretty newb friendly and you can fix your issues for one, and two, can greatly improve your phone;)
good luck