Really, your best bet is to do the research on your own and find what fits your play-style best. Some of the best resources are right here on Psypokes without you having to get other people do to the work for you.
Smogon has a great resource that lists pokemon tiers and lots of popular movesets along with strategy and reviews:
Smogon Diamond/Pearl Pokemon
In the end, you're not really going to be THAT far off base if you've been playing R/B/Y. Just take a look at the guides and references available and you'll do just fine.
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