Check out http://lostpedia.wikia.com
. It's by far the most comprehensive guide to all things LOST.
We ended up watching the entire series all at once via Netflix, and are glad we chose that route. I couldn't imagine waiting 6 years to get through the whole series. Over all, I loved the series, and ended up buying thie DVD box sets after we finished.
The whole gist of the series is this: The island where they crashed is a "plug" that covers the life force for the entire planet. It changes location over time, and seems to be somewhat sentient. Humans have occupied the island for millennia, with a person in charge of protecting it. The scientific research stations were built in the early 70s by the DHARMA Initiative, who accidentally tapped too far in to this life force, with disastrous results. The whole series ended in an alternate reality where all the main characters had eventually passed away, and were reuniting in the afterlife (potentially thousands of years in the future, depending on how long Hurley was in charge of the island in the end).
I thought the series was brilliant, though admittedly I didn't like seasons 3 and 4. I thought they were too soap opera-ish, and nothing was advancing the storyline. We almost stopped watching it because of that. However, the writers got their act back together in season 5, and I found it very enjoyable all the way to the very end. Te season 6 box set also has a very clever epilogue that ties a lot of loose ends very nicely.
I hope that hopes to answer some questions for you. I'm kind of of a LOST junkie, so feel free to ask me anything.