A VPS is a server. You basically have a server of your own which has only 1 IP. This IP is unique though and you're the only one using it. Usually VPS servers have great internet connection with insanely fast internet speeds. You cant switch IP though.
You can connect to the server through remote desktop on a windows PC.
A VPN is not a server. It's also used by more people (multiple people using same IP's) You can use a vpn on your VPS server (which is what a lot of people do, including me). You can also use a vpn connection with your normal PC or a virtual machine. When connecting to a vpn connection, all internet activity on your pc is basically sent to the vpn server (tunnelled), which then sends it to the website you're navigating to. That way, the website you're browsing to thinks you're using the VPN IP. Because of this tunelling, a vpn will be a bit slower than your usual internet connection (especially slower than a normal vps connection).
But if you can find some good vpn servers (hma, strong vpn, etc), you should have great speeds. And yes, with VPN's you can use multiple IPs. For example, HMA VPN is like $10 a month and allows you to change unlimited between 80 IPs. StrongVPN.com is a bit weird because they limit you to like 8 IP changes per month, so they suck.
So basically, upload speed will be a higher on a VPS itself, but then you have only 1 IP (which is unique and you're the only user). A VPN is a tunnelling network which's IP's are being used by multiple people, upload speeds are a bit slower (but still doable) and you can change between lots of IP's.
Now that you're gonna use them for youtube uploading, I'm not experienced with that at all, but I've seen a lot of threads going by here saying it's kinda difficult and that a lot of IP's are blacklisted (maybe including HMA VPN IP's). So you should definitely ask some experienced members about these blacklisted IP's etc. But for now, I recommend you to go for VPN.
