What is x3player?
"After I download a movie torrent file it tells me I need to install x3player to view it. Do I really have to pay for x3 player download or is there some other way to view these x3player movies?"
It is very likely the file you just downloaded contains a virus or other malware that will damage your computer. Most of the so-called video files that run an advertisement for x3players are actually just dummy files meant to trick people unfortunate enough to download the files into damaging their computer. The actual movie or tv show file is almost never what it claims to be.
What to do with an x3player video?
When you encounter any file download telling you to install x3player, 3wPlayer, DomPlayer, or a number of other similar "video players" you should delete the file immediately. Don't download or purchase any software to play the file, just get rid of it.
Who is at risk from x3player?
In general, versions of Windows are the only computers at risk, as the tools for infecting your computer won't work with Mac OS X or Linux, but since you aren't actually getting a video file, your best bet is to delete the file anyway.