Configure vanilla Ubuntu install as a multi-IP secure private proxy server

Hi Guys, I run a windows based VPS service provider, and am an absolute newbie with Linux. That said, I am in need of a comprehensive proxy server that is secure and transparent. I only need a single user to be authenticated (user/pass), but I need the server to be transparent (e.g. when using the proxy, websites do not know its a proxy), and I need it secure against unauthorized access attempts. I will install Ubuntu (or any other version of linux if there is a better one), and provide SSH access. I will leave installing the proxy app to you... I believe Squid may be the best option, but again so long as it works I have no preference. I will attach 2 network adapters to the server, and I will configure the first with a single IP as part of the installation process, but you will need to install the other addresses (there are 64 total) to the server as needed. I suspect this is a very quick job for a skilled linux tech. While playing around I was able to do half of this in just a hour or so, and I know very little about linux and am not comfortable with it. Automated bids will be ignored. Only bids that have comments directly relating to the details in this project will be considered :)