Cron jobs are scripts or programs that will start on a specified schedule. For example, a maintenance task that runs at 3am every morning, or a reporting task that runs on the 1st of each month.
To start up the server via cron jobs you'd need to compile the world and zone servers to unix -- "cron" is a unix utility so I'm assuming that server runs unix.
Also, be sure the sysadmins allow you to run stuff like this on the server. When you pay $5/mo, I highly doubt they intend for cpu-intensive stuff like an EQ world server to be running on their system. To do it without their permission would be a good way to lose that 200mb of space and unlimited MySQL for $5/mo
