Complete dirtbike newbie! Any suggestions for bikes?

[Spiritbeast]

Hey guys... I'm a complete newbie at dirtbikes, heck even at any outdoor sports or such even. To be honest, I'm just the kind of guy who spends most of his time inside on the computer and such, but I'd like to change that and find something to do this summer thats a little more... exciting. When I was younger, I would ride on the back of my neighbor's quad, and loved it. Now I'm older, and want to have something to drive of my own, and that would be a dirt bike (not a quad, probably because my brother loves his motorcycle so much and it seems cool).

I'm not on a very high budget.. I'll say I'm looking for a "starter bike". Anyway, time for that description:

1) your physical size (both height and weight are important)
Er, small. I'm around 5'2 I think, but I'm a little bit bulky at around... 140 pounds.
2) How physical / aggressive are you ?
I couldn't say too much to be honest. Doesn't mean I'm necessarily slow though.
3) what do you plan to ride- MX/SX tracks, woods, fields with friends or ?????
My next door neighbor has 40 acres, and most of it has a grassy, dirtyish kinda path.
4) Do you have any riding experience?
No.
5) Do you think you will race ?
No.
6) Are you mechanically inclined and will you be doing your own bike work?
Nah, but my dad and older brother can do some of that.
7) Do YOU have a preferance to a brand/ motor choice (2 or 4 stroke)?
Huh? (Told I have no clue!)
8) Do you have a dealer close by your home that you might use and what brand(s) does he carry?
Not that I know of.
9) How much ($) do you plan to spend on a bike?
$500-800? (Leaning towards less.)
10) Do you live in California?
Pennsylvania!
11) Your age?
15. (But... I haven't hit my growth spurt or such. I gotta have a bike I can grow a bit into.)

Thank you for any replies.

EDIT: What do you guys think about these generic "some assembly required" bikes? (I would post a link, but thats not allowed!) They seem cheap, but will do the job. That's all I need. I could be wrong though, but any input would help.

 

[derek the 2 stroke]

Id say you should get a ttr 125.Thats a good starter bike and is very easy to ride.Its four stroke and its a trail bike so theyre really reliable.Id say you could get one for around 1000 used.I cant think of one that you could grow into but im 5'5-5'6 and i have ridden ttr 125s without feeling crunched up.i wouldnt buy any dirt bike thats made in china or korea.If you want a good bike get a yamaha suzuki ktm honda or kawaski.Theese are good brands and make the best bikes.Absolutly get a helment.I see alot of idiots riden without a helment.(that usually chnges after they thump theyre heads once or twice)

 

[2 strokes for life]

Spiritbeast, i say a Honda XR100 for starters because its small, light, cheap, matince free(almost), and is really easy to ride. The only down fall is you might need to upgrade by next summer.

 

[sixds]

my friend has one of those 3bay bikes and has had no problems with it. im not saying you should get one, but for like 400$ they seem to be a good deal

 

[flyingfuzzball]

i would recommend not buying a generic bike

you may be fine but i have a friend who thought he would save money by buying one and had almost literly had it fall to pieces while riding. now he has paid almost 2 times the original cost in repairs.

i would say xr100 or tt4 125

maybe crf150F

 

[FunkyD]

remember, he has only 800 bucks to spend, so the crf150 and ttr are probably out. an older xr would be great for feild riding, maybe need some 80 dollar bbr stiff springs for it though.