The question has probably been asked previously, but I am new to bitcoin
and I don't see any help about this.
How do you "transport" a bitcoin environment from computer to computer
so as not to have to reload again all blocks from the internet?
Is it OK to simply copy and paste the "Bitcoin" directory from one computer to the other?
(I am using Windows on a PC)
If you want to move computers, and not use the original one again,
copy everything from %appdata%\Bitcoin\ to the same location on the new computer. Then load the client up on the new computer and check it's working. If it is, delete folder on other pc. Simple.

If you just want to copy the blockchain across, go into %appdata%\Bitcoin\ and copy the 2 largest files into the same folder on the other computer.