Wifi and number of clients on ubuntu

Looking to set up a kolibri network using unbuntu and a laptop as a server. Wondering where to put the $s in hardware most effectively to get the best performance. are we better off to put more into a robust wireless router? I have never configuered a router in linux so dont know how challenging this will be.

Thanks a ton.

Hi, I have a windows installation. Currently we are having problems with users exceeding 25. Dropped or slow connection to the server. I am also wondering if an Ubuntu server can perform better than a windows based server. I have an Amd A8 5600k APU with four gigs of ram.