What should we be praying for?

I'm confused. I still haven't come close to figuring out how prayer works. But then again, who has?

It's ridiculously tricky. Sometimes we regret what we pray for, don't we?

Take this futuristic example: We pray for the raging Category-5 typhoon Pepeng/Parma (or whatever they want to name that blasted thing) to spare the Philippines... and it does! Should we celebrate? Maybe and maybe not. Because the storm has to go somewhere, it proceeds to hit a neighboring country instead, and kills hundreds in the process. Are we to blame for somehow "diverting" its original path? Was the other country not spared because they didn't pray hard enough?

WARNING: Obvious statement coming up...
God knows what He's doing, because He is infinitely smarter than all of us combined.
If that's the case, should we still try to convince Him to change His plans?

I understand that some people easily get offended when a loon talks about prayer logic or anything "blasphemous". Well, nobody visits this blog anyway, so I guess I'm safe. I'm posting this because I took a cue from my sister who jots down notes and posts them on her blog for future reference. I'm not trying to be a smart-ass here, just capturing my thoughts so I could analyze them at a much later date.

How about this: I will pray for Him to get whatever He wants, and for us humans to learn what He wants us to learn. Would that be a wrong prayer? How can I improve it?