I Think My PSU Is Dead

First, get rid of that 6-way splitter and buy yourself a good powerstrip with surge protection. You can easilly Google them and find a good one for less than 20$. Secondly, I like to use an outlet tester to make sure that the outlet is properly grounded. You can get one at any hardware store for around $15. It just plugs into the outlet and lights telling you if it's wired correctly or not. If the outlet isnt properly grounded a surge protecter will be useless. Now, did the spark come from the plug or the PSU? You can test the PSU by removing it from the case, jumping the green wire to a black wire on the 20 pin plug, then plugging the PSU in the outlet. If the fan doesn't spin, its dead. If it does spin then it might have a 12v, 5v..ect. or it may be fine. If you decide to test the PSU yourself, make sure it is removed from the case and is completely disconnected from all the components in you case. You dont need to chance bruning out something else. Oh, and if the fan doesn't spin, make sure that the power switch on the back of the PSU is in the ON position. You'd be supprised how many "repair" calls I did after people moved and accidentally hit that switch.

The good powerstrip that I gave up has an indicator for if the outlet is properly grounded and the ｐｌａｃｅ we live ｎｏｗ gave it the OK before. I　kind of argued with ｈｅｒ that I　didn't want to give up my surge protector, but it is too late now I guess。The spark came from the plug if that means anything.

I am kind ｏｆ scared to try what you suggested drevl． I think I know how to unscrew the PSU, but how exactly do I jump the wires? I don't understand the sentence about 12v 5v, etc. too. Also, yeah I checked the on switch on the PSU.

Don't be afraid of your PSU. Just take a paperclip and unbend it, that will do to jump it. Just take one end into the green wire on the biggest connector, then the other in any of the black wires. It can't shock you or anything because you're only holding one side of the circuit, so if you get shocked, congrats, you just defied physics. If you do that and the fan on the PSU turns on, it may be okay. If it does then you need to test each individual power rail. A PSU provides a number of different voltages, mainly 5V and 12V. Each of these need to be checked that the PSU is actually outputting an acceptable value for it to be okay (and that doesn't even guarantee it). If you've never had experience with a multimeter, now is a good time to get some. Of course, you do this with the PSU completely unplugged from your computer - the only thing that it should be connected to is a wall outlet.