Here I done a silly thing please advice me, is this right way?

Can we use, ASP and ASPX pages in single site and integrated with each other. In dream weaver MX 2004 Ver. 7.0.1 ASP.NET VB server model we don't have User QAuthentication server behavious in this case I want to use one single page in ASP which is post a query string to ASPX page, it is working but is this is correct way......? Instead of writing custom VB code to check the user exists in the database or NOT.

Arvind }<img src=../images/dmxzone/forum/icon_smile.gif border=0 align=middle>