Jstar:
The are a number of explanations for why some Win95 games would install but others wouldn't on that machine. One possibility, as CAG suggested, is that you're missing a file or two that the installers for only some of the games rely on. Another possibility, as CAG confirmed, is the AMD K-6 processor. Lots of software companies in the late '90's, esp. game companies, had to release patches in order to get their software to operate properly with the K-6.
It is interesting that the Janes games causing you problems are from 1997 and earlier. USAF and F/A-18 are later releases from 1998-1999.
Since you bought the computer off eBay, it probably would be a good idea to do a reformat and clean install of Windows 98, as you've no idea what else might have been on there and what kind of state it's in.
If you'd rather not bother with it now, you could install FA on one machine, patch the install, then copy over the files to your Win98 machine. To do the copying, you could burn the files to a CD-R. You could also use a 250 mb or larger USB jump drive, assuming the maker of the USB stick has drivers for Win98. You could also use a ZIP drive, if you've got one of those.
Install FA on the first box, then patch that install using the 1.02F patch:
http://farc.3synergy.net/misc/fae102.exe
Just drop the fae102.exe in the Fighters Anthology install directory and run it. After the patch is finished doing its thing, you're ready to copy.
If you accept the default path for the FA install, here's what you need to copy:
1. The entire C:\Janes directory (which has the Fighters Anthology sub-dir)
2. The following files out of C:\Windows\System (or \System32, if you initially install on a WinXP box):
EA1.UIL
EA2.UIL
EA3.UIL
EAEXEC.EXE
ealtest.exe
EAREMOVE.EXE
On your Win98 box, drop the Janes directory right on your C-drive. Then copy the six files listed above to C:\Windows\System.
Finally, download this ZIP file and unpack it:
https://netfiles.uiuc.edu/ehowes/www/fa/merge.zip
The merge.reg inside contains a few Registry keys that FA creates when it installs. Just double-click on the merge.reg and then click "Yes" when Win98 confirms that you want to merge the changes into the Registry.
You can then create a shortcut to FA.exe (the main FA program) on your desktop.
At this point, you should be ready to go. (Don't forget to put the 1st FA CD-ROM in the drive).
Best,
Eric L. Howes