System Requirements

[WarManiac]

I am very interested in purchasing this version (not Assault Squad 2) but I am not sure if my PC is sufficient for installing and running the game as there is some confusing information about it.
My PC has the following specs:
Desktop Dell Inspiron 570 with CD-Rom
Windows 7 Home Premium with Service Pack 1
Processor: AMD Athlon II X2 45 - 2.9GHz
Installed Memory (RAM): 4.0GB (3.75GB usable)
System type: 64-bit Operating System
Video Card: ATI Radeon HD 4200 (available graphics 1919 MB)
Sound Card: HD Webcam C525 Logitech
DirectX Version: DirectX 11

Although getting old, I very much like my computer so I would not mind a minor upgrade (such as RAM, Video Card or Service Pack) but I hope I would not need a major upgrade or even a new computer. Therefore, can you please advise:
1 - Can I install and play game well as is?
2 - Which of my specs require upgrade or are recommended (how strongly) to be upgraded?
3 - Most importantly, can I even run game on Windows 7 and with my processor? If not, do I have any alternative other than buying a new computer?
Thanks