1. Set up ranks
2. Loop all players and check their ranks
3. If a player's rank is e.g. 100 or below (below VIP level), include him into the menu string.
4. Call out the menu.
I'm not going to write you code just because you're lazy. I already gave you all the steps you need and the resources to do it. Write it yourself or else you'll keep begging people to do things for you and that's not going to happen.
If you don't understand how unimenu works, read the description. Engy added some examples.