Mario tennis: enable "force normal blending" should fix it.
and for the freeze problem I have the excact same problem, so it would be very nice if someone could give a soloution to this problem....
At options-configure plugin(uncheck hide advanced settings)-advanced
Could everyone please test their roms and report at this thread http://www.emutalk.net/showthread.php?s=&threadid=7 all the games that have this pausing issue EXCEPT those set by default at protect memory?(options-settings-advanced-self mod core method) after youve loaded the rom