nice one really it would be hard to buy vista and pc which is vista capable under 30k
as vista official pricing in india is :18000 + 4% and a vista capable PC would cost you around 25-30 k
GO for AMD
amd athlon 64 x2 3800+
Asus m2n-mx motherboard
1 gb ddr2 533 mhz ram
80 gb hdd sata seagate or samsung
a sony dvdrw
any monitor kb mous eof your choice
use a good quality 450-500 w psu SMPS
and try utilising on a graphic card ex:7300 gt
these all things will cost you around 32000/-
if you want near 30000/- then decrease your ram to 512mb and it will work ...
your winxp sp2 will cost you 4600 + 4%
a graphic card = 5500/-
board processor=10000/-
ram=5000/-
hdd=2200/-
sony-dvdrw=1900/-
monitor 15"=3200/- 17" = 4200/-