Aches and pains are common in the course of exercising, at least if you're doing it right :)
They say no pain, no gain (whoever "they" are) but who wants to live with the pains of your grandparents? I've been walking around on achey legs wishing to God I hadn't done so much yoga and wall-sits and trying to remember why I work out in the first place. I've heard that foam rollers are good to soothe aches and pains, but you only use those right after exercising, so what about the day after when the aches appear?
According to SparkPeople, massage, icing and stretching are best, which all sound reasonable. the main thing however is not to just sit around to your muscles relax (as if that were ever an option). Yoga, stretching, and walking are all good, they increase circulation which speeds muscle recovery. Any aches that last for more than five days however are more serious, and you should probably confer with your physician.
Post-workot aches, or delayed onset muscle soreness, are not necessary to prove you've had a good workout though, they're just microscopic muscle tearing!