No real fire wall issues as far as I am aware.
As you would expect access to sites of certain natures is blocked.
Hotel will charge their normal rate for a local call which may differ by hotel, around BD0.035 per minute (i.e. 50% mark-up); you may need a new cable, although UK phone-jack is standard, the wiring is not quite the same so you might need one making up when you get here. If you already have an ISP & email account, why not see if your provider subscribes to a roaming service (GRIC dail is one example), then you can access your exisiting account(s) via a local telephone number initially before deciding what you want should you be in Bahrain long term.