I'll second this.
The general rule I recommend for people new to reddit: When you sign up, you'll be automatically subscribed to a few default subreddits. Never, ever, ever read the comments on any of those posts. Unfollow the ones that might not be relevant to you (e.g. /r/gaming, /r/funny, /r/news, whatever), and then look for alternatives to the rest.
If you find the concept of Ask Reddit interesting, look at /r/TrueAskReddit for a moderated community of people answering real questions with real answers.
If you're a gamer, look for a more narrow community. Try /r/ps4, /r/wow, /r/steam, and so on. Instead of a reckless free-for-all of foul-mouthed teenagers, you end up with thoughtful, relevant, and moderated communities. For example, this post where top-level comments are restricted to mentions of the current Steam Sale games, with threads descending from those for discussions on each game:
http://www.reddit.com/r/Steam/comments/1t9f6n/rsteam_should_...
There are local subreddits, like /r/Vancouver, but they're hit or miss; Vancouver's is generally a circle jerk of transit-hating, car-hating twits complaining about Asians buying up all the condos, so your mileage may vary.
If you get suckered into the 'hive mind' behaviour of 'what do we hate today?' then Reddit is going to make you a worse person, and I feel as though this is the general case for a lot of people on Reddit: it's where people go to let loose about things which they only hate because everyone else hates them too and it gives them something to feel a part of.
Reddit is a microcosm of the internet as a whole: your experience with it will depend on which communities and topics you're exposed to.