if i am hosting 2 sites with the same hosting account (hostmonster) will it make my sites load slower. is it better to host them with 2 different accounts or no?
Chances are it's a shared hosting account anyway. You're probably already sharing the server load with 50 or more other sites. Your two sites won't impact it.
there is no impact unless one of your sites is serving a lot of traffic or doing questionable things. in these cases your actions will propogate to all other users on that ip.
Your good to go. The amount of sites isn't an issue it's the amount of bandwidth, traffic, db connects, etc... Best of luck with your sites!