If you are looking to rent from a
DVC member for specific dates that you want to travel, you are essentially asking to rent their points, but your thread would begin with "Reservation Wanted . . ." You would provide your resort/villa type request, dates you want to travel, etc, and anyone who has the points to rent to you can respond.
If someone is offering a "reservation for rent," that means that they have already booked a certain room for certain dates, and if you are interested in that particular room for that particular time, you can respond to them.
At the top of the Rent/Trade boards there are some very detailed threads about how you should go about posting there. They have very specific rules about how you title your thread.
Hope that answers your question. I have been both a renter and an owner, so I have a good idea of how it works on both sides of the transaction. It can by nervewracking! Feel free to PM me if you have other questions - I'd be happy to answer them.