All of them meet your requirements... Best to go to the shops and try the Nikon, Canon, Sony, Pentax and Olympus entry-level DSLR cameras. See which one feels the most comfy in your hands, then do some research online for reviews, etc. Then look ant the marketplace section here for a second-hand set.
In addition to what bro Rashkae mentioned, do note that there are a lot of good cams up for sale in the Personal Classified section and note the characteristics of each system before buying. Don't buy something just because of the brand and others ask you to do so, get something that suits your needs.
Not easy to decide but you have to put that in mind.
I think if you a serious hobbylist , maybe you want to consider a lower mid range series of the brands . But you prob need to research more on the functions of each camera and how they affect your shooting.
For e.g . Some cameras may not have spot metering , how that affects u ? Or some camera has inbuild image stabilisers , while some are build onto lens . Some camera are on the 1.5 crop sensors , while some are on smaller ones and some are full frame.
I guess the questions goes on and on and most bro will tell you , if you are a starter , any brands probably suffice , and you will see the difference when you start to understand more about the equipment , probably by then you will not need to ask anymore
Personally , I places value on ergonomics and ease-to-use , which was really one of the key deciding factors that made me decide which DSLR to buy.