Welcome to Pentax Forums Andriy.
I was supposed to be in your city at the moment, but bad roads and a few other factors forced me to put the trip off for a while
Like everyone else new to the SLR world I'd advise you to just have fun with it for a while.
See if the pictures are what you want. They just might be.
When your comfortable with it feel free to try AV or some other mode, and go from there.
You probably won't have to do much tweaking with any software, so I wouldn't worry about that either.
So just have fun, and let the learning process begin.