You can use this i tried it for
VB 6.0
Create one text file as test and write
!DB2 CREATE DATABASE TEST !
Then
create one batch batch1 with followin command
db2cw db2 -td! -f <textfile path which you have created(test)>
Then Create one more batch file batch2 which contains followin command
DB2CW @<first batch file path (batch1)>
and now finaly you can call batch2 from dot net then it will create database
i hope it will be helpfull for you...................