In my opinion 14 months is hardly old. I am running Windows 7 on a six year olds machine.
It is not very difficult to download an ISO image of windows 7 installer from
Official Windows 7 SP1 ISO from Digital River « My Digital Life. The ISO image can be made universal by applying "eicfg Removal Utility" on the image. You have to take care that it is the exactly same image (32-bit or 64-bit, x86 means it is 32-bit) that corresponds with the original version that was on it (Starter, Home Basic, Home premium, Pro etc) when you got the Computer. If it is a Laptop then the product Key would be on a sticker in the base of the Laptop. You then activate it with the same Product Key with which it came to you.
The Network Adapter can be found and easily downloaded by a Google search for "conceptronic 54mbps usb adapter driver download" in case it doesn't get installed with Windows 7. For starters try at
Free Driver Download for Conceptronic 54Mbps USB adapter - American Megatrends Inc. N355.
Also please keep in mind the advise tendered by Karlsnook and please fill in the System Specs to the best of your knowledge.
You should be up and running in a short time. Best of luck.