BMX - new bike!

I want a bike mostly just to ride around and for a little excercise but I also mite want do a little light bmx type of riding too once in a while. I am a skateboarder so I don't know anything about bikes so I don't know what kind of bike to get. I really want a bmx bike but I also want to be comfortable riding around sitting down sometimes too when I am going for a ride. I am 5'3' and normal weight range for that height. Is there such thing as a blank bike setup? Like a blank board for skateboards? I was gonna buy a diamond back but I don't really want like a basic bike, i would rather have a better one just in case i decide to get into more tricks but I know im not gonna get too serious with it and it will still be used for riding too. I also dont know what size bike is best for me and my size either. any suggestions?

just wanted to add this: im looking for some info on what riding style of bike and size is good for me? I don't know anything about brands either so what brands are good and not so good?

Do any of your friends ride BMX? Try out some of their bikes and see how they feel, or test ride some down at your LBS; after you've ridden a few different ones you'll start to get an idea of what you like or don't like about them. Don't feel like you need to ride with the seat all the way down just because everyone else is doing so -- put the seat somewhere that suits you, and don't worry about lowering it until it gets in your way while you're doing a trick. A 20" will be fine.

While you're at the LBS looking at the bikes, check out the price range of the "serious" BMXs they have there (ie the ones that aren't sitting with the little kids' bikes):
- The cheapest ones here will be OK for what you want now, but they won't leave you much room to improve.
- The most expensive ones will depreciate in value very very quickly, so I'd steer well clear of them. If you end up not really liking it and want to sell it, you won't get much more than a couple hundred dollars no matter how much you initially paid.
- Pretty much everything in between will be fine for now and will leave you some room to improve, without losing you too much money if you change your mind and want to sell it later. Test ride as many of them as you can and buy the one you like best.

You could also see what you can find second-hand: you'll usually be able to get a higher quality bike than you would've been able to afford (or willing to pay) otherwise. The downside is it can be hard to tell a good one from a bad one if you're not already experienced, and even a good one might need a bit of work before it's ship shape.

I'm an OG!

I'm an OG!

Pointless. But anyway, just test ride some to get the feel. But the recommended brands would be DK, Kink, Fit, etc.

ok, i have been looking around and doing a little research to learn more and I heard a lot about the dk six pack. what is so good about this bike? there is a bike at a shop ive been looking at also an eastern traildigger and it has the gear thing on the left side which i like. i don't know the correct terminology cuz like i said im a skater but i think the frame is not 100% chromoly or whatever you call it but im not sure about that because the one i looked up online didn't have the gear on the left side like the one at the shop. does anyone know which traildigger it is, any info appreciated. maybe im wrong about this, like i said, im a skater so i don't know what all the **** means when im reading about the bikes when i look them up. i know the six pack is probably better but is the eastern one bad? because for some reason i like it. it is 350. at the shop

again i forgot to add something, i want to know what these bikes are for, freestyle or what? what is the dk six pack for and the eastern one? its called a traildigger so does that mean its not freestyle? I need mostly a freestyle bike but is there something in between freestyly and jump bikes or a bike for both? i will moslty be riding on the streets with it but sometimes go to a park and try stuff and maybe sometimes try some dirt jumps

The DK Six-pack is made for pretty much everything. The Traildigger is not a very good bike, considering it's not full chro-mo which is really important. Most bikes are made to do more than one thing such as trails, street, and park, except flatland bikes.