When searching for inline skates there are many things to consider. 
-Are you just going to be skating around the lake? 
-Are you playing hockey?
-Are you going for distance? 
-Are you jumping ramps and sliding down handrails? 
-Are you just looking for something fun to do?

For all these options you want to look for a durable inline skate with plenty of ankle support.  Look into brands such as: Mission, Bauer, K2, Solomon, Razor, or Rollerblade.  These are all reputable brands who produce quality skates for at least one of the above categories. 

For skating for recreation you will want a skate with bigger wheels and more than likely a brake on the back of one the skates.  If you are looking for going distance you may want to consider a skate with 5 wheels.  These skates usually do not have a brake as they are aimed towards a more advanced crowd. 

If you are looking for hockey skates you want to look for a lighter skate with a light weight frame.  These skates are almost always lace-up boot only.  Hockey skates may also have different size wheels on the front and back of the skate.  This helps with your speed and maneuverability while playing.

If you are looking for skates to jump ramps and slide down rails with (aggressive skates) you will want a skate with lots of ankle support, but they also need to allow you to bend your ankle a little bit.  These skates do not come with brakes as they are aimed at more advanced crowds and they will get in the way while performing tricks.  Aggressive skates are not made for speed.  They come with smaller wheels to make them very maneuverable but slower.

For all forms of inline skating wrist guards, helmets, and knee pads are highly recommended!