So I am interested in renting a dedicated server, with root access.

Could someone explain exactly what root access is and how it is used? Is it similar to FTP access with read and write?

On *nix systems, root access is just administrator access (the default administrator user is called root). It basically means that you have full read/write access to any system service, configuration or device. You don't need root access to run a Quakeworld server, however.

got root?

Root access means you must set up everything for yourself, sometimes servers are preconfigured, but most dedicated servers in such form are just in the simplest configuration and you must set up everything on your own.
So root servers are for people that know how to administer dedicated server.

root access means you're allowed to make the machine fail to reboot.
probably it'll be a virtual server anyway... but hey.

What it means is that if you don't like FTP, you can install an ssh+sftp server instead... as well as actually use the standard ports for those services. it means that you need to apply security updates yourself, but also that you actually can. it means that if something wrong happens on the server, it is guarenteed to be your fault, and not the fault of someone else running some application that stole 100% cpu time/fork bomb.

by the way - ftp sucks, use sftp

scp?

For someone who has never used root access, would it be a bad idea to rent a dedicated server and try?

Depends on the distro you choose for your server

It will win a windows server operating system.

I recommend you rent a VPS instead. It is much cheaper and should be a good playground. If you screw up, you can easily reinstall the OS.

Yeah, I don't really need root access and I have no experience with it.

I'll have to search a bunch of sites that offer VPS at a decent cost.

Heh, I'm thrilled no one has asked you what you are gonna install on the server? That will most likely be the determining factor if you need "root-access" or not.

You just can't say "I don't need root access" if you have no experience. It's nothing more complicated than you have full permissions in the OS.
Compare it to the Guest-account in Windows and an Administrator-accout (equal to root-access in *NIX)

You usually don't say "root access" when speaking of Windows, that is more likely to be an *NIX operating system.