You can get it to run ok, you will (or more than likely have graphic issues still)
I can still run on an old Compaq with a AMD2300 and a Nvidia 5200FX with 1 GB ram !
Something I know about rent to own places . *I just cleaned and fixed and upgraded to the best I could a friends they paid 2500UDS total for one that sounds almost the same (and was only 399 new! )(from Rent a center- the same as aronsons if I recall right, or at least close) When they made their final payment they did take that PC in and exchange it for a new one in the sealed factory box. (Before you finalize your agreement try and get them to give you a new one and posibly it will be a better PC. the rental place already made the cost 4-5 times from your payments and they loose nothing, its worth a try, just stand firm on them )