Yes Alisa......it seems like it would be a HUGE change but it really isn't. Just like the other ladies said.....Mac is so much more user friendly. Just take it one step at a time.
Unzipping....I don't use a program. I just double click on the zip file and it unzips it. No biggie. I personally don't use Safari but I have used them in a pinch and it does automatically unzip any zip files you download. It is an awesome feature. Safari comes installed on the Mac.
The Fontbook (also comes installed) is AMAZING! I love love love it! It is SO easy to install your fonts and it puts it in your PS/PSE automatically. LOVE IT!
This will all probably make more sense when you actually have it in front of you and you are able to play around with it. It did take me about a week to get use to where things were located on my Mac. It is different but not harder. KWIM?
I am excited that you got a Mac! You will be so glad that you did it!