After I take a picture, my Samsung TL240 takes a long time before the flash is ready to take another picture. It did not do this for the first few weeks I had it, but now it does it all the time. I have changed the settings, but I can't get it to be any different. It didn't come with any sort of instruction booklet or software, so I don't know what to do.

From your description, it is most likely that the camera memory is full or you are using a very big memory card on it.
It is just like a computer, you see, on a computer, the more items you load onto it, the slower and less responsive it becomes to whatever actions you intend for it to carry out. In the same way, the more pictures you take or items you load on the memory of the device, it is prone to respond to actions or commands in a slower manner.
The most effective remedy for this problem is for you to copy majority of the items that have been stored onto it to a computer and free up some space on the memory of the camera.
This will help it in the sense that there would be less data to process and then it would be able to respond actively to commands.
On the other hand, it might not be the physical and visible files that are slowing it down. In other words, it is not always likely that the pictures on it are responsible for this defect. It might be due to the fact that repeated use have caused it to pile up some system files and this is choking up the memory.
In this case, the only solution is to do a complete format or reset of the camera.
Hope this was helpful? Please comment for more information and thank you for using fixya.