If I were you, I wouldn't "install" Kentico on your production server. There's no reason to install the actual software on your server. Install that locally on a machine and deploy the code to the server. Doing so for someone who has done it many times before would take less than an hour. For someone who has never done it, could take 1-4 hours or more if they don't know what they are doing or have never setup a site.
Regarding importing a site, is this an 8.0, 8.1 or 8.2 site you plan to import? If not, you'll have to go through an upgrade process first:
- 5 -> 6
- 6 -> 7
- 7 -> 8
- 8 -> 8.1
- 8.1 -> 8.2