You should use njal.la or shinjiru for the domain as they won't do much about reports (you must choose certain TLD's if you're doing highly illegal things, otherwise your domain could get seized).
When it comes to hosting, you should probably get a dedicated server if you're going to be handling those amounts of people as it'll provide good performance and good speed overall (doesn't have to be a big machine, with $40-100/m you should be able to find something good enough).
You should get the server in one of these locations preferably as they usually don't mind DMCA violations as much as other countries: Netherlands, Bulgaria, Russia, Singapore, or Malaysia. The Netherlands will probably offer the best speeds.
Use Cloudflare too as it'll make your site faster and protect it against loads of different attacks, and yes, they're American but they pretty much ignore complaints (from personal experience).
To host the files you should use a site like bayfiles.com or similar. Hosting them yourself will cost you a lot and involves a lot of risks too. If you still want to host them yourself, get a dedicated server with a lot of storage, buy another domain, use Cloudflare and upload them there.
