Most of the actors (Jon, Rob, Theon, Joffrey, Daenarys) aren't really kids (remember thekids on the show are 18ish, played by 20-something actors, while in the book they were 14ish), so they won't age that much. Some of the rest play characters that mature in the story so some aging will work. I don't want to potentially spoil who does or doesn't die, so i won't go into details, buti can think of only one where it might be a problem. And for that character a 7 year run or a 10 year run won't make any difference, as thatactor will age the most early on.
The 5 year break was GRRM's original plan for the beginning of book 4. but after a year of writing he gave up on it, because he didn't like putting so much emphasis on flashbacks. that's one of the reasons that book took so long to come out, he completely started over on it. there won't be one at the beginning of book 6 (leaked sample chapters prove that).There could be one part way into that book, but i highly doubt it. The reason GRRM stated for having one is mooted by book 5.
Besides, if there are long waits, it'd be at the tail end of the series, when the handful of kids have mostly grown up already.