A few questions about comments and products

I am completely new to WordPress, so I hope these questions are fairly simple to resolve.

When I go to my home page (blog), it says that the comments are closed. How do I fix this?

Also, I can’t seem to get a “products” page on my site (I’m using MarketPress Lite). When I roll my mouse over the “store” page, the only links are for checkout, transaction results, and your account. How do I get a fourth link for a list of products?

And one more: How do I make a title for my home page? My browser simply has the URL as its title.

Thanks!