Ah yes, the 'we are going to drive you around the twist' kids.  Got 2 here as well, and it seems that while they hear me, they are not listening.

I start out with a gentle voice, pleasant and asking.  This gradually increases in volume and the tone becomes more stern.  Often, I have to end up really 'barking' at them before they will listen to me.  Maybe that is what your boys need.

Every child is different and it can take time to work out what is going to work the best.

My five year old does the same things - but at least there's only one of him!  We work on the 1...2...3 system and they know if they get to 3 they are punished, so mostly we get to 2 and he will do it.  However we get days where he just doesn't want to get out of bed, doesn't want to leave the house, get dressed etc....  Some days I am stern and that works, other days I have to baby him along and that works, but I have to try and work it out and some days I get it wrong. 

When he is like this I will dress him myself (I sit on the lounge, or on the floor, slide him onto my lap and do it, so I am not picking him up) and if he even refuses to let me do that I will put him in the car in pjs and he dresses when we get there.  Sometimes I ask him what will make him get a move on - last week he wanted mummy to stay at preschool and that was good as I was down for parent help anyway, yesterday he wanted nutella toast for breakfast (a big treat) so I agreed if he got himself up and moving.  I have to play it by ear, but if I make a threat I have to act on it, otherwise he will remember and push it again the next time.

I don't know if anything I have said helps, but I know it is a lot harder with 2 as the acting up is intensified by each other, so can you tackle each one separately and talk to each one about their personal behaviour?

What about taking another tack entirely and starting a reward system.  At a quiet time when you can talk with them, tell them you need their help to get dressed etc. (whatever you want them to do that they're not doing) and that each time they do what you ask without trouble, you'll give them a sticker on a chart.  Whenever they earn 5 stickers they get some sort of reward.  Make sure its something they would really like.

They're obviously smart kids, and by staging these sit-ins they're getting what they want (delaying getting dressed etc).  Maybe they'll be smart enough to work towards rewards for you.  Also, if that's working, if they start acting up again, you could take the stickers off the chart so they go backwards as well as forwards.

I would agree with izzy if they aren't listening to options I wouldn't allow it to be discussed at all my four year old tries to have a bit of a run away and (fake) "I don't like school" she gets picked up stood in front of me and dressed with no words spoken whether she be's difficult or not. Sometimes they just need to learn when mummy speaks jump and no amount of timeout or whinging or playing is going to change what they should be doing when you say it needs to be done. If you consistently tell them two minutes, ignore them, then when two minutes is up dress them regardless of what they do with no further comment they should start to relize that nothing will work they are getting dressed. Good luck with it, parenting I find with young or older is more of a power struggle don't let them get the upper hand or your doomed lol

My 3 1/2 year old is this way especially in the mornings when I tell him to get dressed so I can drive him to pre-school. Then again at night about eating and getting dressed, brushing teeth, etc.

What works for us most of the time is a timer. At night we lie down with him before bedtime and he used to never let us go. I say I will lie down with him for 2 minutes and then when 2 minutes is up, he doesn't want to let me go anyway. WIth a timer, I set it for 5 minutes and when it goes off that's it. It's worked wonders.

Then just yesterday we went to the county fair. He loves trains so we took him to this train exhibition tent and of course he didnt want to leave. I then asked him if he wanted to stay 1 more minute so I can set my watch, and of course he asked for 5. So then I did and when it beeped we were off. It works. :-)

So maybe using a timer would work for you too.

Another suggestion is to keep yourself from engaging. Keep a stern face and do not converse until they've done what you've asked.

Good luck.

i used to babysit a child like this. she wouldnt eat her dinner, wouldnt do her homework (she was 6). refused to come in when we asked her to.  she was that bad that the only way she learned was a smack on the bottom. she soon learned that if she did it the first time no smacking.  as harsh  as it seems it works. but first tell them if they dont do wat they are told then they will get a smack. if they dont listen the second time then just smack it will shock them into doin it the first time.

sorry to give such a harsh advice but if it comes down to it then it might be the only way.