need advice on computer program

Hi photographers-
I am very excited about getting a new camera. I decided to go "whole hog" and get all that extra stuff to make nice macro photos, which I have always wanted to do.
I have a windows computer, and a big backup drive. My computer guru says it is big enough for what I will be doing.
I doubt I will want to do a lot of editing in the computer, beyond cropping and red eye reduction and other simple tasks, but it is possible. I want to take nice pictures, not become a computer graphic artist. Right now I use the canned program that came with the computer. I liked the one in my apple computer a bit better, when I had that, but I will not go back to Apple because I need a Windows computer for work and do not want two computers.
Maybe I should just stay with what I have. I would also like to be able to scan in my old photos and slides from the analog age, and maybe make some photo albums for people. It sounds like with Picasa I could just hit the send button and it would be printed up which sounds nice.
I am OK but not great with computers, but not afraid of technology and would probably take a class. I also like the "for Dummies" books.
Or-
Picasa seems a possibility, or Adobe Photoshop. Lightroom seems to be a fancy version of photoshop?
Do you find that shooting in RAW format is useful? I have always used jpeg images and it might be a lot more complicated to shoot in RAW.
Thanks for any advice you might have.