Easy: Buy new=
CPU = E2160 = $75
Motherboard = ECS G31 mATX motherboard = $55
Video Card = Powercolor 3450 (Passive) = $45
Case = Aerocool M-40 = $80
Power supply = Thermaltake TR2-420w = $40
Ram = Buy from Vortex or pay a lil more, OCZ 2Gb kit (after MIR) = $30-50
Burner = Any, most are around $30-40
Keyboard/mouse = Any
MCE remote and IR receiver = Ebay? approx. $20-30.
Thats pretty darn close to your budget for a decent system thats upgradable easily with a newer video card and up a 1333 45nm Intel processor.