Aerosols are normally permitted, in both hand luggage and hold luggage, as long as the contents aren't themselves prohibited. (e.g. aerosols containing lighter fluid or paint would not be permitted).
Aerosol cans are designed so that, even in a vacuum (i.e. with zero external air pressure), the internal pressure should not be high enough to fracture the container but, for added safety, it might be better to keep aerosols in an environment where the pressure outside the can is not greatly lower than that inside it. This would suggest that a pressurised cabin would be a better place for an aerosol container, rather than an unpressurised hold.
The regulations regarding prohibited goods are largely dictated by international air transport regulations, so they should be much the same for all airlines. Here, for example, are the lists of prohibited items for Ryanair flights:
Cabin baggage:
http://www.ryanair.com/site/EN/faqs.php?sect=bag&que st=prohibiteditems
Hold baggage:
http://www.ryanair.com/site/EN/faqs.php?sect=bag&que st=prohibitedchecked
Chris