What is Litecoin?
Litecoin is the result of some of us who joined together on IRC in an effort to create a real alternative currency similar to Bitcoin. We wanted to make a coin that is silver to Bitcoin's gold.
Litecoin manages to maintain the unique traits and attributes of Bitcoin, while adding to the mixture CPU-specific mining and a 2.5 minute block rate. This means that Litecoin doesn't have to compete for the used up computational cycles of your graphics card if you're already mining Bitcoins, but can work independently on your processor.
We'd like everyone to get their chance at being an "early adopter", so we've preannounced Litecoin several days ahead of launch day for you to be able to prepare your mining setup on our Testnet. There have also been no more than two blocks mined ahead of release; the genesis block followed by a block to verify it.
- litecoin.org
And yes, I'd say i5 is good for mining LTC. At least above the average .