Network performance

Apologies if this is not the right forum, but I have a question on network performance.
I have an 16 ports 10Base-T hub connected to the main server and also connect to the 24 port 10/100 switch hub. The server is running very slow if someone is download or copy files. I’m thinking of upgrade the server hub to be 10/100mb switch hub also. I don’t know if these going to speed up the network proccess. Please let me know all your comment will be appriacated.

Thank you in advance