Broadback wrote

I am considering replacing my desktop computer. what is the best way of
transferring data from my old one to the new?

Depends on how things are organised on the computer you are replacing.

If you are running a reasonably current version of Win, the files
and settings migration wizard does a decent job of doing that.

If you are running an ancient version of Win it gets more complicated, but
still possible. I wont bother to spell out how unless you say thats the
case.

If you are running linux its also not that hard, but again not
worth spelling out the detail unless you say that is your situation.