Hi.
Unclear about some stuff.
SW B2 do you mean the 2005 or the 2017 version?
RC - don't recognize - what is it?
You have an older machine (2007) which should run almost any game that is earlier, but may not run later games well. You have an older Windows version and some newer games may not work with that.Maintenance becomes important - like cleaning out dust and if temperature problems, cleaning old thermal paste and replacing with new.
Being a Dell, one of the things you should do is to run the excellent diagnostics available from them on the website.
http://www.dell.com/support/home/us/en/04/product-support/product/inspiron-531s/diagnose
If you can, you should also download and run Belarc Advisor - it will tell you a heap of stuff - for free.
https://www.belarc.com/products_belarc_advisor
Your C drive does not have enough free space, so you should remove what files/programes you do not need, run clean up and run defrag.
You are limited as to expansion - cards must be half-height.
You may wish to go to Dell website and download the system manual.
Please tell me what model and version you have for the video card - I am unsure what you have - eBay can give some great bargains. There may be an issue with ATI drivers which needs to be checked.
Also, please say where you are located and what your budget might be.