Wordpress is a pretty easy system to get to know. You've obviously got your install done. And you've managed to install a theme and enter some content.
I've been working almost exclusively in Wordpress but have a background of about 10 years in various web design and packages. You'll be pleased to know that for very little investment you can build a very comprehensive set of tools and do some fun things with Wordpress.
I would start by recommending that you choose how to approach your theme. If you don't want to get your hands dirty with messing around with Wordpress then I'd advise that you buy a good and well supported theme. I started with Elegant themes which allows you a great variety in layouts for a very low price. Good forum support and well written themes that are being updated. If you strike problems you can get knowledgeable help pretty quick.
There are others available but I would stick with well supported themes. It is crucial if you want to develop a website without mucking around with Wordpress. If Elegant themes doesn't strike you as appropriate I would try [Themeforest. You might pay a little bit for a theme there but some of the themes are again well supported and come with many extra options built into them. Things like sliders, shortcodes (for quick styling), galleries etc. Go to the popular items and view the downloads, stick to the top items, they are the ones that are well supported by the authors and will retain support. I'd recommend [URL="http://themeforest.net/item/udesign-wordpress-theme/253220"]U-design](http://themeforest.net/) as a good flexible theme. Yes you pay for them, but you save yourself a lot of time and stress searching through forums or getting your own hands dirty in Wordpress (although it is almost impossible to avoid if you want to customise).
Function-wise Wordpress has many add ons and plugins. Again you'll find a wealth of free and some premium ones. I use a combination, free where possible, pay a few dollars when I want something to trust or very specific functionality. I use a variety of suppliers for this, but codecanyon.net has some insanely useful bits. I again suggest you rank by popularity and look at how long ago things were written and the comments to gauge how well supported the author is. Do note that some of these sites do not guarantee support but almost all quality authors stand by their products. They're easy to pick.
For disabling comments easily (WP grew out of a blogging background so they're ON by default) check out Disable Comments in the Wordpress vault. Very simple and will disable site-wide in a couple of clicks.
Social media options are plenty, your best bet is likely to use one in a widget area. Depending on what you use many themes will incorporate it as a freebie.
Hope that helps. I searched for a long time to get my tools set up and I regularly use, here are some of them:
Headway themes (more of a visual framework approach than theme).
Backup Buddy (for backup and migrating sites easily)
Styles with Shortcodes (easily worth the investment)