Naomi stuff doesn't work in Mame yet. If you can't get it running with the Naomi emulator then its either not supported, you haven't set it up properly or there's something wrong with your CHD.
Since you haven't provided any info on what emulator you're trying to use, what you've done so far, how you've set it up, what error messages you're getting, what PC and operating system its running on or anything else, its impossible for anyone to give you any help.
Virtua NBA is supported by Naomi emulator but i cant get it to work and I also tried virtua nba rom and other required files like the bios and the chd file on mame32 for windows xp (but now im using windows 7) with 1gb ram and 512mb video card. The problem is when the mame emulator loads for 100% but it only loads until 88% and then the emulator stops working. What did i do wrong?