There is no use in upgrading a Windows 95 computer to 98, it will just run slower if it only has 16 or 32MB of RAM, and the PC doesn't have USB support anyways, so you don't get the extras that 98 offers. Just convince her to get a $299 emachines or Dell.
I deal with Windows 95ers daily, so I know more about this topic than most, and I know its not worth the upgrade. Just get a new PC.