They're old enough to travel with; my parents were taking my sister and I from Canada to France and Italy by the time we were 3 and 5. The only major problem I can see, from what you've said, is how Kyle screams a lot; give him some time to grow out of it.
One of my uncles (in the USA) has 2 kids a few years older than yours; he's been thinking of taking them to Europe to visit my family (we live in Switzerland now) for the last few years; he wants to make sure they're old enough to remember the trip.
Some family friends visit from Canada on a more or less yearly basis as well; two of them have have visited twice with a child younger than Kyle, and that's worked out perfectly well.
It may be easier when you're visiting friends or relatives; I don't know, as that's the only way I've seen people I know personally travelling with young kids.
In short: your kids are old enough to travel with! What you need to do is decide what you want from travelling, for yourself, talk to Erin about what she wants, and think a bit about what your kids can get out of it (Emily might be old enough to ask; it might be interesting to see what she'd come up with if you set her loose with a tour book), and take Kyle's sensitivity into account.  |