help need a new video card

i am looking for a new video card for my emachine it is like 5 years old i wont to play games online like dc online i will put up specs do not need a top of the line card so if you can help ty if you need more lit me no the game specs are
• Operating System: Windows XP 32-bit
• Processor: 2.4+ GHZ Dual Core
• RAM: 2 GB
• Video Card: NVIDIA 7800GTX+ or ATI x1300+
• Hard Disc Space: 30 GB
pc specs are Operating System new – server roles System Model
Windows 7 Ultimate (build 7600)
Install Language: English (United States)
System Locale: English (United States)
Installed: 11/5/2011 2:38:25 PM GATEWAY W3507 500
System Serial Number: GRD6A50005505
Enclosure Type: Desktop
Processor a Main Circuit Board b
2.67 gigahertz Intel Pentium D
16 kilobyte primary memory cache
1024 kilobyte secondary memory cache
64-bit ready
Multi-core (2 total)
Not hyper-threaded Board: Intel Corporation D102GGC2 AAD70214-201
Serial Number: BTGC63901EZ1
Bus Clock: 133 megahertz
BIOS: Intel Corp. GC11020M.15A.2010.2006.0817.0956 08/17/2006 i do not no if that will help