Budget?
here you go, two options:
CPU - http://www.newegg.com/Product/Product.asp?Item=N82E16819104244 - $31.50
Motherboard - http://www.newegg.com/Product/Product.asp?Item=N82E16813135224 - $48.99
HDD - http://www.newegg.com/Product/Product.asp?Item=N82E16822135106 - $43.99
RAM - http://www.newegg.com/Product/Product.asp?Item=N82E16820140003 - $15.99
Case - http://www.newegg.com/Product/Product.asp?Item=N82E16811156011 - $19.99
PSU - http://www.newegg.com/Product/Product.asp?Item=N82E16817182006 - $20.99
DVD Drive - http://www.newegg.com/Product/Product.asp?Item=N82E16827101131 - $18.99
Total=$201
or
CPU - http://www.newegg.com/Product/Product.asp?Item=N82E16819103535 - $57.40
Motherboard - http://www.newegg.com/Product/Product.asp?Item=N82E16813138264 - $59.99
RAM - http://www.newegg.com/Product/Product.asp?Item=N82E16820145026 - $50.99
HDD - http://www.newegg.com/Product/Product.asp?Item=N82E16822135106 - $43.99
Case - http://www.newegg.com/Product/Product.asp?Item=N82E16811180030 - 31.99
PSU - http://www.newegg.com/Product/Product.asp?Item=N82E16817153023 - $36.99
DVD Drive - http://www.newegg.com/Product/Product.asp?Item=N82E16827101131 - $18.99
Total=$300
just through in the OS and any monitor. Id take the second option, because its more solid and balanced