I keep seeing both terminologies under the same menu but I don't understand the difference between them.
Feedback Solution consists of topics (ideas, questions, problems, thanks) that are designed to be used in public to collect feedback and for other users vote for them. They could be used in community portal, embeddable widgets to get customer thoughts.
Help Desk solution consists of tickets - they are only private requests collected from such support channels like email, facebook, twitter, contact form on community portal or embeddable widgets. Tickets are designed to help customer or the whole company only privately. So all emails would be converted into tickets along with replies.
All topics and tickets are combined into Requests in the agents interface with Reports and Queues that you can built in order to get various requests based on custom conditions. More details could be found in Working with Requests & Queues
If you don't require any topic type or even all the types from feedback or tickets, just switch them off in Administration - System.
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