I'm considering joining Netflix but the site doesn't give enough information to convince me unless I first start the free trial. Can anyone answer these questions I have?

1. I'm only interested in Netflix to view old tv shows on my PC. I'm NOT interested at all in the DVDs by mail. Are all of their DVD selections also available to be watched online, or just some?

2. On the price plan (http://www.netflix.com/HowItWorks) in the "Hours Instantly on your PC" column, there's two different types: a choice between unlimited hours included and 2 hours included. What does this mean?

3. Is there anything I should be made aware of before starting the free trial?

4. Any other comments or recommendations?