I can help point you to some of the information:
-- Pentium 4 class or above with 1 GB RAM: You can look the CPU/RAM configuration of your server (Proteus) using the procedure described in this DH Wiki Section. Note that on a shared server, all the RAM is not available for your use. Using DreamHost PS you can reserve specific amounts of RAM/CPU for your exclusive use.
-- OS: RedHat Enterprise Linux 4 or above, Fedora Core 2 or above: DreamHost runs Debian Linux
-- Apache version 2 or above: DreamHost runs both Apache version 1.x and 2.x configurations, with most "newer" installations being Apache 2 (Tech SUpport can move you to a either an Apache 1 or Apache 2 version if you require one or the other).
-- PHP 4.3.11 or above with PEAR support: PHP 4.4.x and 5.2.x are available by default with limited PEAR support. You can install and configure your own PHP version for use on DreamHost with whatever PEAR support you require/desire.
-- MySQL 4.1.18 or above: All DreamHost MySQL versions are now at version 5
-- Curl support: cURL is installed and supported
-- GD Library version 2 or above: installed and supported
-- ffmpeg-php version 0.5.0: Not installed by default, but you may install it yourself.