Looking for a High-Security Web Server?!?!?

My dad called me today with some great news from work! His company is getting a new website! I have no idea how but I guess the site is all setup. He asked me to help him look for a server to buy at his workplace. I have no idea what kind of server we are looking at, but he gave me some specs that they NEED to have on this server. This server needs to host an "In browser application", needs to be secure (Secure as a banks server as it will hold very personal information!), needs to be RAID based, needs a large amount of hard drive slots (terabytes upon terabytes of data), Lots of ram (around 120 average users on at a time all using this web app), and we need it under $10,000 preferably. Would we need a web server or dedicated server? It will be a site people go to and type in their information to get to the web app.

Email sent to my dad:

Web Server for EBS.

Please advise on a server to run the self-service portion of EBS Timesheet.

I am not looking for the basic system requirement but rather what it would take to run with and employee base of 100-150 users. We want to make it available outside our domain. We have concerns with security but setting it up on a single machine should provide us the security we are after.

Processor model(s) and speed

Operating System

Memory Requirements:

Hard drive specs

Network

Required applications installed on server/computer

Ran out of characters! Ill update!!!!!!!