Not all plugins are compatible with the highest 3.6.x of Moodle.
Do you re-call which plugins ... listing would be nice, but considering 'several' was mentioned that might not be possible.
Would help to know a little bit more about your setup ... would make a difference in suggestions.
What operating system is the Moodle hosted upon?
Where is the site hosted? Provider?
Do you have some sort of 'backend' access to view files? Could you locate the moodle code directory?
As far as "worse than Joomla 1.0' ... Joomla 1.0 sucked! Not really a fair comparison. And that comment coming from one who has hosted/administered Joomla sites.
'spirit of sharing', Ken