Recommendations for a new desktop

[Maladict]

Since the old one seems to have bought it, and I don't want to spend more money on it.
Looking in the 700-800 euro range, I'm completely out of the loop so all the numbers don't mean anything.
Are these any good?

Candidate A: 700 euros

HP Pavilion p6350
Intel Core i5-650 (3.2GHz, 512KB, 733MHz)
6GB DDR3 SDRAM
1TB SATA 7200 rpm
DVD+/-R/RW LightScribe
ATI Radeon HD 5450 1024MB
Windows 7 Home Premium 64
1 year warranty


Candidate B: 700 euros

Local store-built pc
Power supply: Recom 450 Watt ATX
Motherboard: MSI P55M-GD45
Processor: Intel Core i5 750
Video: MSI GeForce GT220 1GB
Memory:    4 GB DDR3 1333 MHz (2x 2 GB)
HDD: Samsung Spinpoint F3 1 TB (SATA II)
Software: Microsoft Windows 7 Home 64-bit (OEM)
2 year warranty


Candidate C: 750 euros

Dell Inspiron 580
Processor: Intel® Core™ i5 Processor 750 (2,66 GHz, 8 MB)
OS: Windows® 7 Home 64
Memory:   6.144 MB 1.066 MHz Dual Channel DDR3-geheugen [3 x 2.048]   
HDD: 1 TB SATA-harde schijf (7.200 rpm)   
Video: ATI Radeon™ HD 5450 1GB DDR3 graphics
4 year in-home warranty