Urgent!! How to get rid of red, dry knees & legs? What causes it? [pictures inside]?

For the past few years I have been constantly having red knees.
i've tried exfoliating & moisturizing.. They both didn't work well.
When I've moisturized my knees, they were less red but went back to red afterwards plus really dry..
And it doesn't help with the fact that I've got some scars on my knees from when I was little from maybe falling over..

As for my dry legs, I think I have some razor bumps, and can't seem to get rid of them:(
Most importantly, they look VERY dry..

http://i53.tinypic.com/1222bgx.jpg
http://i51.tinypic.com/2vbvklf.jpg
http://i52.tinypic.com/2sacjkj.jpg

For all these reasons above,
it means that I can't wear any dresses/skirts without wearing either tights/leggings, and have been hiding my legs for the so many years! I'm going on Holidays in a few days in a hot country, and want to wear some dresses without leggings/tights!

Please help!