[christophilus]

Record: I'm not hiring now, but if I was, I wouldn't necessarily hold any of this against you. Heck, I wouldn't even know about it, since we don't do any kind of criminal screening. The main concern I'd have is whether or not you can do your job. If I did know about your past, I'd want to be sure that you would be clean moving forward. I think (and hope!) you overestimate the negative impact on your career.

Ageism: the main problem with hiring older people is that they are expensive relative to new grads. The other problem is that they are often perceived as being inflexible and lacking desire / drive.

Expense: It's a trade-off. Sometimes, you need the expertise, and it's worth the extra $$$. Sometimes, not. But in my opinion, it's almost always worth paying up (within reason) for experience. I tend to err on the side of reverse ageism, which is unfortunate for junior engineers who interview with me.

Drive: This perception is a false one, but it is pervasive in HR departments from what I've seen. If you can get through HR to the actual technical interview phase, I don't think this will hold you back, as you're clearly engaged and interested.