There is a huge amount to be gained by going from 3-1/30 to 3-1/63. The graphis are totally different and much much better.

when you say you burnt the largest of the file, are you saying that you put the 200MB file on the disc? If so, that was wrong. You do not copy the MDF or IMG files to the CD!

The largeest of the two files contains the CD contents - it is like a zip file. It needs to be opened with eg ImgBurn and then burnt as a complete CD.

Changing to a Mk4 is super easy: unplug the Mk3, plug in the Mk4. That simple.
But upgrading the software is even easier :-)