Today I woke up to this: 2.49 BTC sitting in the balance field. Man, I knew Bitcoin wasn't worth 20$ anymore! Let me tell you, this made my day, probably, my week or even this entire year!
Is there anything I need to do now that I'm holding a pretty big amount of Bitcoin? I've read that hardware wallets are the safest, should I buy one? Is there anything I need to know?
You are extremely lucky. You should have purchased few lottery tickets as well on the same day when you had discovered this balance in your bitcoin wallet. The amount you have found in your bitcoin wallet, is more than my mortgage amount. I want to write a similar true story about my dogecoin locker, but I am not able to find where I have kept around 40k dogecoins.
Hardware wallets wouldn't be required as you are using a bitcoin core wallet. But ensure that you always keep enough space in your hard drive for the blockchain to sync.