In essence, if your swing hits a baddie you hit them. If you hold the block when they hit you, you block. The effectiveness is measured by your stats, naturally. Each class of weapon (blade or blunt) swings more or less the same way, ie, a longsword the same as a shortsword but not the same as a two-handed axe. Some neat little combos tie into the system well. The best discriptor for it is solid. It feels very, very solid. Where it balances two handed swords vs daggers is in fatigue. Once your fatigue hits rock bottom your swings don't do very much at all. One can swing a dagger all they like and it'll take much, much longer to tire them out than with a claymore. The health of your foe is shown as a bar over your crosshair, so it's always there in front of you. Hit animations are pretty good, especially at higher levels where a swing from your beastly magic warhammer sends a bear flying into the sky. There's no lock-on targeting but it's rare to lose your bearing thanks to the first person perspective. There are times that you're overwhelmed but that's to be expected - anyone trying to fight six skeletons while being bombarded by fireballs is going to be in trouble
Detailed enough?