heh, i usually let it get out of hand too at the 300+ mark too. loading up old tab sessions is a pain, though i may switch from chrome to firefox now that firefox doesn't background-load tabs anymore. much more efficient. (chrome can easily use 10GB RAM)

when you first log in as a new user, Windows 8 shows you a mini-tutorial about using the hot corners. you literally can't miss them, unless of course you missed it by logging in with someone else's account.