People who own a point and shoot camera eventually want to move  to having a 
DSLR. Other reasons could be you want 
clearer images, you  want more control over your camera or you want to become a professional  
photographer.
Whatever your reason, you can start with having an  entry level 
DSLR. This is lighter than the real 
DSLR and is more  affordable as well.
So first things first. Consider the 
brand and  you have many to choose from - 
Canon, Fujifilm, Kodak, Nikon, Pentax,  Panasonic, Olympus and Sony. Most share the same features but if you  often travel and take 
photos during special occasions, you need to pick a  model that's easy to operate but at the same time one that can ensure  image quality.
For those who are serious in  getting into 
photography, the two famous brand names you should consider  are 
Nikon and 
Canon. Most, if not all, professional 
photographers use  these brands.
As for the digital camera  components, the 
camera sensor is an important consideration if quality  images are your priority. Basically, there are two types of sensors -  the CCD and the CMOS. The CMOS is present in the latest cameras today  owing to its lower production cost while the older models utilized the  CCD which provides better quality 
photos.
Consider  as well the camera body. This is essential particularly if you have  plans of purchasing high-end accessories in the future and because you  will need to get accessories such as the lens that match the body.
Most  entry level 
DSLR cameras today have quality plastic bodies. Weather  sealing, however, is what gives the higher type or the professional 
DSLR the edge. Hopefully, this will be made available for the entry level  models in the future.
When it comes to  material, you have a choice between getting a metal and a plastic body.  There's no doubt that the metal body is more durable and allows for  better heat conduction notably while shooting videos. 
Nikon and 
Canon  manufactures both metal and plastic bodied 
digital cameras.
Some  people often prefer cameras that have bigger megapixels thinking that  it will give them better 
quality images. But this is a misconception.
Do  understand that you need a higher megapixel camera only if you would  like to print large 
photos. This is because 
printing a large size image  requires more megapixels to produce clearer and crisper photos. A higher  resolution is also ideal if you do extensive post processing of your  images such as cropping without affecting the quality.
But if you just want to snap and store photos on your computer and share them online, then a 3.5 to 5 megapixel camera will do.
The  camera's affordability should be an important consideration. Know that  you will not only be spending for the camera body alone but for other  necessary accessories as well so make sure that you get only what you  can afford. Calculating your expenses will help you choose the right  entry 
DSLR camera that fits your lifestyle.