The simple answer to your question is yes. There are a lot of differences between the two. The following link takes you to another topic where this question is already answered. If you have more questions after that then ask away.
Bonboonman may be correct on the price but that isn't the issue. Being that Viva Pinata: Trouble in Paradise is much newer than Viva Pinata, it would make sense that it is still going for 30-40, depending on where you shop. The issue is which one you want to play, again, just go back to the link I posted earlier in this topic and read what Bonboonman and I said about some of the differences. There are more in depth descriptions of both of these games if you read the reviews for them on GameFAQs reviews.
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