Help! choosing a breed

Good breeds for first time owners (of course, they all need proper training and socialization):
Field Spaniel
English Cocker Spaniel
American Eskimo
Cavalier King Charles Spaniel
Portuguese Water Dog
Leonberger (if you like big dogs)
Pug
Shih Tzu
Boston Terrier (if you don't get a hyper one)
Most important - don't buy from a byb or puppy mill.  Go to a reputable breeder, or adopt a puppy from the shelter that has been temperament tested.
And, don't overlook a rescued older dog that's already housetrained and a bit quieter.
You can train an older dog - it's never too late!!! 

Hey - I'm just vouching for my breed here. Shasta's an American Eskimo Dog (Eskie) and I think they're great. There are three sizes, toy, mini, and standard (shasta's mini) so you can take your pick. They are absoloutly beautiful and are bred as companion and circus dogs, which means they will love you forever and are really intelligent. VERY playful... love to use their minds, find long playtimes far superior to long walks. Ok... the thing is is that they are HIGH shedding. But if you were thinking about a husky anyways, that wouldn't be such a problem. If you get one, be prepared for people thinking he's a samoyed pup. They look exactly the same, only way smaller. They are pretty rare and they might take some searching to find a breeder.
 
If you decide to get one of the breeds on your list, be careful. Some of those breeds are known to be irresponsibly bred, ending up with horrible temperaments (chows are pretty stuck-up anyways, no offense to any owners out there). And never, ever, buy from a pet store, they sell pups from puppy mills and you will be supporting a horrible trade.
 
Whatever breed you get, congrajulations on gaining an amazing companion!

Just wanted to note that while I want to be clear that I would NOT recommend a Chow to this or a first time owner, my Chow is a wants-to-be-with-me-al-the-time dog.  I haven't taken a shower alone when in the same house as him in the 11 years I've had him. He whines if I go in without him. In fact, both he and my yorkie both follow me everywhere. It's a running joke in the house about my little parade of three dogs behind me[]

I have to say, my first dog- chow x eskie- was pretty much the PERFECT dog for a first-time dog owner. (Other than her health issue- severe hip dysplasia.) And I've known a lot of chow MIXES who have been pretty close to perfect- laid back, calm, easy to housebreak, highly tolerent of the things chows aren't supposed to tolerate, etc.

I'd suggest the OP look at YourPurebredPuppy.net - at the moment, it's my favorite online breed guide. While I don't agree with EVERYTHING the author says, I think she's right on about most breeds.

Mom said to get a small or medium sized dog, but I want a dog that won't go around doing what it wants for the rest of his/her life (like my cousins,he barks at people and acts kind of spoiled).

 
Then you most certainly do NOT want an akita.

I know what you mean, we have a little maltese and my 11 yr. old said she wanted a dog she could play fetch with.  So we know some people with different breeds and a friend of ours has a border collie that we just love.  So we did our research on the internet, well I did the research and they are high energy loves to play so we picked one up from a farm and at first it was tough going, but she's getting better.  There are so many breeds and the five you picked are really different.  Remember beagles like it outside and they'll bark alot and howl.  You'll need a big yard for a big dog to run around.  Research the different breeds you're thinking about carefully and good luck!

I can not say I would suggest any of the breeds you have mentioned.  All expect the shih tzu need alot of attention-exercise.  I am not a fan of small dogs so it is hard to say but you might want to look into as mentioned above the english spaniels or king charles just check your breeder carefully and ask for references.  If they do not want to give you any walk away no matter how cute the puppy.  And while I do not condone the mutes that are now called designer dogs you might want to check into a poodle mix.  These you might even be able to find one in a shelter.  My mom about 20 years ago before they were designer had a poodle-yorkie mix that she absolutely loved and seem to be everything you are looking for.