If you feel up to it, and you want to do it, I say go for it. Just remember: no job is as secure as you want to think it is. So if your main factor in staying at your current dead-end position (sounds like it's dead-end at least) is job security, you're asking for trouble.

From the ouside looking in, it's simple. The start up. I'm sure the thought is somewhat frightening of leaving a comfortable job, the current routine. The "unknown" is always scarier than the "known" even if the "known" sucks and you hate it. But from one guy stuck in a very similar deadend job situation to another.. jump on it. You will regret it for a very long time if you don't take the chance because you'll always be wondering "what if...."

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Or as Alienz said, the opportunity could be used to leverage your perpetually upcoming promotion at the current job if job security at the startup is a worry. You could just say you weren't looking, but this great opportunity fell into my lap and since things are kind of at a stand still here I'm thinking about taking it. See what they do.

Two years with no salary adjustments or reviews should be the reddest of red flags you have ever seen in your life. I don't know how old you are, but you typically make the greatest career advancements in the 30-40 year old range. If you're in your 30s, you are now a couple of years behind where you ought to be. You're making anywhere from 5-15% less just because of no adjustments and inflation. Take the new job, stick with it for at least 18 months. If it goes belly-up or you hate it, at least you'll have the experience and the salary history.

You should not only leave, you should set the place on fire when you do.

Oh, you should probably rot in the cozy office job.

Magnus and Hemidal seem to have the experienced advice you're looking for. Just be sure to get your entertaining resignation letter approved by us first.

Sometimes not taking a risk is more of a risk than taking it.

Being stuck in an unfullfilling job is miserable. If this new startup is people you trust who are dedicated in making things work there's no question you should be with them. Not only are the opportunities for advancement huge but the overall morale change will just plain make you feel better about everything.

Unless they're already publically traded, no, you didn't. While there are ways for non-traded companies to value options, they're not useful to the person receiving them. You may have the option to buy 10,000 shares at a dollar a share, but that right may not be worth anything. Take it from someone at a non-public startup - don't assume your options are worth anything. Be pleasantly surprised if they are.

I feel for you. But I think you already knew the answer when you posted the question. That's a good thing, and we disparate communities are hear to provide moral support in times like these.

I'm giving you the benefit of the doubt: you're good at what you do. If you've never made the scary leap into entrepreneurville before, you owe it to yourself to make it. I feel for your parents pressure -- I know it well. I've made the leap, and had it both work, and had it bite me in the ass, and I wouldn't have traded it for the world.

In my ten and half years of LARGE corp. companies, the best way to advance is to leave for two years. After two years send your resume back to the original company and VIOLA! You are now your boss' boss' boss. ie you are two or three levels above where you were before. The poor smucks who stick around get known as the go to guy but never really advance like they should because they are too busy fixing problems to get experience to advance. If I knew of of job offering the same economic rewards but with more opportunities to go I would jump.

Startup. If they're already gotten several runs of venture capital then I'd say that there's some strong promise.

Startup.
Just make sure you can cover your son's medical stuff still.

From reading your stuff, I have the horrible feeling that your boss is going to fire you soon at the current place.

And the new place will probably be a great experience for you as well. The only reason not to go is security at the current job, which doesn't even sound that secure, get the hell out of there and take the stapler with you.

I'm just going to say stick to your current job to try and grab some attention, while the obvious thing to do reading your post is quit and go for the startup. Duh.

I'll take this from a different angle. Although I am still young, I have seen first hand what happens when you stay with a job that you are unsatisfied with. Every day becomes just another grind. You punch in, watch the clock tick by while you half heartily try to perform a job you are jaded with. You work with your boss who you begin to develop ill will against because he keeps giving you the run around about advancement on your promotion. When you keep going through those steps every year, you become very dissatisfied with more than your job. Having to trudge it out day after day, year after a year will begin to impact yourself as a person.

An old friend of mine once told me that if I did what I do love to do for a living, then everything else would fall into place. If you feel that this new job could re-invigorate yourself and make going to work a pleasant thing, then go for it. Forget the pay, the commute, the "new-ness" of the company, the office job you left behind and go for it. If this is the kind of job that you could see yourself looking forward to performing that daywhile commuting there in the morning, then don't think twice and go for it. If you are happy doing your job and enjoy it, then everything else will fall into place.

Also I agree with Logan. If you tell your boss you are leaving, your promotion will all of a sudden will just have come through.

No question about it; go with the start up. I tried promoting a guy at a former position and it too months to get the title and salary to line up. It's BS and I bet there is some hesitation on your managements behalf.

If you still have some doubts, confirm the new job via an offer letter with a start date and give notice. If your current company is serious about you, they will counter. Then you can make your decision.