You can’t be sold on Linux. Anyone ‘sold on’ or ‘lead to’ Linux isn’t going to stick with it. The desire to learn to use and be productive with Linux is purely an internal one. Selling you on it would be like trying to push you into a religion. For this, you need to sell yourself on Linux. Install it, run it, make it your daily system for a few weeks or months… then you can decide if it is for you. The questions you’ll need to find answers to are, but not limited to:
Will it run the software I need? You mention PDF’s… Viewing non-encrypted PDF’s is no problem. For encrypted PDF forms that I’ve seen from some government sites, I needed Windows or Mac to fill them out reliably. I was able to do some within Wine, but that wasn’t stable enough to depend on.
Be aware there are desktop choices. Linux comes in many flavours, some can present and work similar to a Windows desktop workflow, some more similar to Mac (but not quite), and some are just either heritage UNIX styles or just Linux unique. Finding what you prefer can take some trial and effort.
I suggest Linux distributions that offer disk encryption (and be sure to use it). If you were my lawyer, I wouldn’t want the documents we share to be left around un-encrypted anywhere.
Check out some Linux periodicals, as well. They can help wet your whistle with reviews on various Linux distributions and often some introductory articles on software and How-To’s. If that kind of thing interests you, you’ve already half sold yourself on Linux.