It's a VPS so you can probably get away with pretty much anything you want. It'll depend on how much traffic your site gets and how heavy your VPN traffic is, but it won't hurt to try anyway.
Apache vs Nginx vs Lighttpd is a difficult question to answer. It will depend on your site more than anything, really. If you are using Wordpress for example, it's really designed for Apache. If you are mostly serving static content, maybe Nginx or lighttpd would be less resource intensive. There are more complex setups, like Apache behind Nginx, too. But if you don't know what you need, then best just stick to something simple for now. Maybe someone else can come up with a good reason to prefer one over the others. Do you have a CMS or something in mind already? That could help to know.
It might be a good idea to run the VPN and HTTP servers on different IP addresses, if you can do that with your VPS. That would help keep the VPN hidden from port scans on the HTTP server's address, and vice versa. It's not strictly necessary though. OpenVPN doesn't use the HTTP or HTTPS ports if I remember correctly, so there should be no conflicts running both services on the same server/address.
I went ahead with Apache for my CMS website and I kinda got it to work but in the end my host helped me set it up and add more IPs so I could split services up. Ended up with a 2nd VPS on the side for a discounted price to seperate my services.
I went ahead with Apache for my CMS website and I kinda got it to work but in the end my host helped me set it up and add more IPs so I could split services up. Ended up with a 2nd VPS on the side for a discounted price to seperate my services.
I went ahead with Apache for my CMS website and I kinda got it to work but in the end my host helped me set it up and add more IPs so I could split services up. Ended up with a 2nd VPS on the side for a discounted price to seperate my services.