My internet speed is solid at around 10-15 mb/sec. How long would it take for me to download the entire blockchain for the original bitcoin wallet?
Time taken to verify the blocks can take more time than downloading it. Your peers' latency and speed can also affect your blockchain download speed. Even if you have lightning fast internet, if your peers have slow internet, you would likely to take a longer time to download. You can always use a lightweight wallet if you prefer not to wait for so long.
That can always be fixed by temporarily setting maxconnections=1 and connect=(fast server). You avoid getting all the 'orphan blocks' that way as well, from multiple nodes sending you blocks.
You can use 5.9.24.81, 75.102.27.50, 107.155.104.194, or 199.233.245.125 right now, if you like