Hope you like shopping!
There are some great restaurants around and the local food is good. You gotta check out Mamma Noura's, great shwarma etc
Depending on your nationality you can go to some grrrreat parties in the diplomatic compound where all the embassies are. This is one of the very few outlets for fun in RUH. The UK / US & Aussie embassies are some of the best. These are the only places where you can really let your hair down and drink real booze; not the local moonshine.
Ironically some of the drunkest nights I have had in my life have been in RUH. There is a great little bar in Seder compound too, bout 15-20mins drive from city centre. They have regular discos and if you get in touch with the compound manager Richard (nice old Brit guy) he can sort you out with entry.
As a previous poster suggested, learn how to brew, it's not as hard as you might think and with practice you can make some pretty decent stuff.
The driving is insane, no other word for it. Recommend you get a driver and use him for a few weeks til familiar. RUH is a mass of low level tan coloured buildings and once out of range/sight of your 2 major landmarks (Kingdom Tower and Faisaliah Tower) you can get hopelessly lost as the whole city looks the bloody same!
Keep water in your car in case you break down somewhere in the summer time as the temps will touch and sometimes exceed 50C.
Mutt is dead right one the employer front. For one guy that his treated well there are several that are treated like camel sh1t so do some homework if you can.
Enjoy
D.O.G