NOT computer savvy at all and need Ibook G4 help

My son is getting ready to deploy and someone donated a ibook G4 A1055 - she said it needed to be upgraded - ???? - I took it to a Apple repair shop and they said it would not need to be upgraded and if I really needed to I would have to use Leopard - Again ??? but it really doesnt need it.

He will be using it as a means of communication with family and watching movies and internet.

Can someone help me and tell me what I need to do?

Also its missing the white box to the power supply - I was going to purchase one online and I dont know if I need the 45W or 65 W - Help again.
Thank you

Well shoot I wish I could answer more but I have no idea what I would be looking for and the battery is dead and I dont have a power cord to plug in. LOL

Well if it doesnt come with a webcam I can get one for it. We are planning on using skype so thats good to know.

The place I went to wanted $80 for a power cord - I found them on ebay cheaper. I am in the US
Thank you for your help -