You can start by looking at this article: https://help.dreamhost.com/hc/en-us/articles/215280058-Virtual-Private-Server-VPS-overview-
in a nutshell, on DreamHost VPS you get what you get on the shared hosting service, with automatic upgrades of base packages, web server, added security, etc. In addition to shared hosting, you get improved memory and CPU isolation, faster SSD disk, persistent processes, etc.
Monitoring is a different beast. The VPS doesn't offer specific monitoring tools unfortunately. If you know of any monitoring tool that can be installed without root privileges, please let us know. I'd be happy to test it and write a tutorial on how to install it.