I think most of the hosting accounts are inbuilt with your requirements. I am using cpanel-11 and In that there is an option called Fantastico(as artycrow said), which has all the options for your forums, and It has many inbuilt options for gallery and many other things. As you said you are going to use your site for a short period of time, you can use gellihost for free hosting, or there are number of hosting accounts available for a very reasonable price. You can choose any of them.