It all depends on what tools you're using on the site, and what hosting control panel you're using to administer the hosting account.
You've gotten some good advice so far: always make backups, always test an installation before putting it live, and always upgrade in small steps so that you can backtrack if necessary.
Everyone has different strengths and weaknesses, so it's not easy to say "This app is easy to use" or "That app is hard to use". Just remember: ask questions when you need help. We're all newbies at *something*, every single day. (And at the rate software manufacturers play musical interfaces, quite often we're old pros one month and frustrated newbies the next...on the same app. [I really dislike manufacturers who do that constantly...])
Lesli Schauf, TLM Network
Linux and Windows Shared Hosting since 2002: Scribehost