I got it working!
For future reference, if anyone is using a Dell Latitude D610 with the intergrated 915GM graphics card, you can use this link to run Counter Strike: Source https://www.mpgh.net/forum/105-counte...ac2-proof.html.
Just download MPGH Public Hack.rar, unzip it, and double click on the MPGH.exe file and you're good to go!
Thanks Credzis!