Downloading movies legally isn't worth it; you may as well purchase them at a store. If you are running Windows, Amazon.com has "unbox", which is a full-quality download service. Unfortunately the files are "locked", so you can only watch them on your computer (i.e. can't burn them to a DVD), and they cost virtually as much as the regular ol' physical copy. If you've got an iPod you can download TV shows and movies through the iTunes store. The price is a little better (as you are downloading something really low-res), but again the videos are locked so you can't watch it on a TV, say.
You are currently living through a transition. The policy of the MPAA strongly discourages downloadable media. This is more than evident by the restrictions placed on your purchase and the price you are paying for it. Think of it this way: You could buy Movie A at a store for $15 on DVD. That DVD is a physical medium that cost money to make, and even more money to ship to the distributor and to the retailer. That's figured into the price so the studio still makes a profit. Once you own that DVD, you can take it to a friend's house and watch it, you can burn it to your computer or iPod to watch it, you could use it as a frizbee to entertain your dog. Now for $14, you could download Movie A from Amazon.com. The quality of the video is the same as the DVD, and often times you even get the extra features as well. It cost the studios a fraction of a penny in bandwidth for you to download the video. There were no shipping costs, no manufacturing costs, etc. Essentially 100% profit. Rather than passing the savings along to the consumer, they make the product even crappier. You no longer have the option to watch it at a friend's house. You don't even have the option to watch it on a TV in your house. It is forever glued to your computer. Worse still, you are stuck using Amazon.com's software to play it back! You can't even queue it in your favorite media player!
Now let me switch gears here and accuse you of misdeeds against
the man.
You should never be put in a position to worry about the trustworthiness of a site... unless you are downloading movies
illegally. It would be like worrying whether Best Buy is actually selling you the movie, or whether it is just a virus in disguise. Balderdash! And while it is noble of you to not
mind paying fees, what legal alternative exists? Seriously? Outside the public domain, you have
pay for each thing you
buy. That's how capitalism works. Which leads me to suspect your real question is, "How can I safely download movies illegally?" That, my friend, you'll have to Google for.
