I note that the standard recording format for video for Jaksta Media Recorder 7 downloads is .wmv, but under settings this shows that other formats are available.
Having selected .mp4 I note that it still records in .wmv. Why is this?
JMR downloads in the container format that is most suitable for the protocol. This is most likely going to be mp4, based on the most common streaming protocols today.
JMR's DVR functionally however uses wmv as this is very quick to record to. DVR'ing is intensive (or can be) and therefore a container format that is quick to write to is used.
If you have selected JMR to convert after downloading or recording, then that is a separate process and the original recorded or downloaded file will still be there. Up to you to delete if you no longer require the original.