Did a fresh installation of Windows 7 sp1 last night. Ran windows update at 10pm-ish and the were 207 critical updates. Left it running over night for 12 hours and it's still running now currently at update 174.
I have 47Mb fibre the machine has 2GB RAM, a 2GHz Core2Duo and an SSD so it's definitely Windows that's at fault.
Upgraded my son's laptop from Mint 18 to 18.1 at the same time and it took less than 10 minutes to download and install the entire operating system and upgrade every application he has installed.