Dea Fred n.
This is not the free accoutn at Netfirms is it? I had an account (perhaps I still do) at Netfirms that had an internal server error every time I tried to do anything because they place a limit ("throttle back"?) on the server time that free accounts can use, making the free accounts vertually useless for scripts. They told me that I would be able to run movable type on their servers, but as soon as I pressed the update site button I got a server error.
Other than that there are the php requirements as defined in the installation documentation.
Thirdly, Moodle requires a number of PHP settings to be active for it to work. On most servers these will already be the default settings. However, some PHP servers (and some of the more recent PHP versions) may have things set differently. These are defined in PHP's configuration file (usually called php.ini):
magic_quotes_gpc = 1 (preferred but not necessary)
magic_quotes_runtime = 0 (necessary)
file_uploads = 1
session.auto_start = 0
session.bug_compat_warn = 0