Most games written for Windows 3.1 or Windows 95 will run on Windows 98. Games that were only written with Windows 2000 or later in mind will usually not run on Windows 98.
only in compatability mode
Since there isn't a UNIX 95 or UNIX 98 per se, I think you are referring to Windows 95 or Windows 98..
Windows 95 & 98 Windows 95 & 98
Do you mean the games say "compatible with windows 98?" and you have Windows XP? Games are backwards compatible. Meaning, if the games say "windows 98", windows 95 is ok (anything before windows 98 will work). But it is not forward compatible--Windows 2000, windows xp, etc. will not work. does this answer?
Windows 95 is 17 years old and windows 98 is 14 years old. this answer will get updated every couple of years.
Windows "9x"
Yes.
Windows 95 to Windows 98, and then to Windows XP
Yes, the Saitek X52 Flight Control Joystick is compatible with Windows XP.
Windows 98 came out in the year of 1998 that's why it's windows 98.
No. Only Windows XP is supported; Windows 95/98/ME/2000 are not supported and are not planned to be in the future.