Weight training is not just for body builders. Anyone who wants to be truly fit should weight train as it helps to give you a toned, more sculpted look. How far you go with it is up to you.
You can weight train using either machines or free weights. Free weights include dumb bells, disks and bars which weights can be slid onto. You can use the equipment to strengthen and reshape your body or even just use your own body mass for exercises like press ups, chin ups etc.
The pros of this type of training is that it makes you stronger by increasing muscle and bone mass. It is also the best way to add shape to your body.
There are no real downsides to weight lifting unless you are doing it incorrectly. Some instruction is a definite must.
If you are just out to get stronger, generally 20 - 30 minutes twice a week will be enough. To really change the shape of your body much more time will be required.