100 users at same time is huge load. You are technically talking about millions of hits per day. Did you really mean 100 users at same time????? I don't think any shared webhosting like hostmonster or its parent Bluehost can support it.

You would need multiple dedicated servers in web farm to support it. On high level, I would say one dedicated web server for 10,000 hits per day. so, if you are talking about millions of hits per day then you are talking about hundreds of servers.

DO YOU REALLY MEAN 100 USERS AT SAME TIME?????