I am considering buying a computer as a surprise for someone. The CPU and graphics are :Intel® Pentium® Processor T4400 with dual core technology (2.20 GHz, 1 MB Cache, 800 MHz FSB) and NVIDIA® GeForce® 9100 MG DirectX® 10 graphics with 256 MB shared memory.
In general terms, any graphics card that uses shared memory isn't good enough for games playing. The best ones come with their own built in memory. You don't say how much memory is installed but you should be looking for a minimum of 2gb.
In short no, if you really want to get into gaming on a PC, a Graphics Card with shared memory will hinder your gameplay, regardless of how much RAM the system has. Get a GPU with it's own memory.
Trust me, it will save you a fortune in the long run.