You can keep your current OS, Casper. No problem with it.
When OVH will send you the e-mail, they will give you the information to connect to your server via SSH and via RDP. A remote desktop client allows you to access your server as if you were in front of it (with the nice windows graphics and everything ).
If you think you won't be able to do the setup, do not hesitate to send me a PM. I can install uTorrent, its webui and configure everything. I already setted up a few OVH servers for FST members.
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