Both are on sale on Steam.Are they worth $5 each?

I remember playing Stronghold as a kid and thought it was amazing, I'd buy it for $5

Do you mean Stronghold 3? If so, I wouldn't recommend it. Easily the worst game in the series. If you're talking about the others though (or a multi-pack), I recommend Crusader, which I consider to be one of my favourite RTS' of all time. (And I made a video showing it off which you can watch http://www.youtube.com/watch?v=q2Fv6TtYRY8)

I think it's Stronghold 1 and 2 and the dlc.