Before being self employed and having children hang gliding and paragliding was what I lived for.. I have two wings ( one of each) sitting round slowly deteriotating. There is nothing like it in the world, the feeling of climbing wing tip to wing tip with a buzzard or red kite as you thermal up is unbeatable. The little beeb, beeb sound of a vario as you go up still fills me with excitment.. The memory of not being able to get down in rough conditions is still the scariest thing I've endured..
HG's are faster and as you lie prone you feel like superman, when conditions get bad you can just pull in the bar a fly fast. They are bit and not much fun to carry up a hill, so generally restricted to sites with roads. Towing up to height is however viable from trucks, winches, boats, or micro lights. This opens up flying in different wind directions and conditions etc..
PG's are slower and you fly in a sitting position, as you can't go as fast as a HG they have a smaller wind window and will get blown out before the HG's. The wing can also colapse in rough conditions which is not great if close to the ground. You can carry them to the top of a hill and in a car and plane however.
I would say PG's are slightly easier to lean to fly and a bit cheaper. 7 to 10 days good weather should get you the pilot rating. Go to the BHGPA.
As to the dangers, both HG and PG have potential. Both will fly on their own but you would hurt lots on either if you were to try to land like without imput. PG pilots get more spinal injuries as you can land on your bum, HG pilots face and arms are more common as you have a control frame to hit.
The biggest issue is however it becomes all consuming. You sit on the top of hills waiting for the wind to, change direction, drop, pick up, etc, etc.. If you bomb out and your mates fly off, you hate them. If the weather looks good you have to go fly as you can't miss a chance. Weekends with nice sunny days can be spoilt as too windy, or not windy enough and you just sit around on a hill.
If you've got the time do it... But go learn somewhere sunny. I learnt HG while in Florida and PG in New Zealand. Green Dragons do trips to spain I think.