Great Man you can do it as long as you have current aspx website in vb.net,but needs bit hardwork for changing some functions of classic vbscript functions to vb.net,but later it will be mess,confusing and really tough to handle it.
It sounds like you are asking "can I write ASP code in a file with an ASPX extension?"
The answer to that question is " yes/no/sort of."
If you put a <% %> section with code that is CLR compliant in an ASPX page it may very well work. However, you should avoid it because it goes against the whole UI/logic separation technique of ASP.NET. Furthermore, if you tried using functions unique to VBScript in the ASPX page it would definately break.
What it comes down to is this: Either just write a regular ASP page that you are familiar with, or learn how to write ASP.NET the correct way. If you try to munge the two together you will only taint your ASP.NET learning and will complicate things for yourself in the future.
so i suggest you to upgrade classic asp to asp.net ,no problem if it will take one week more becaise asp.net is now great SERVER SIDE TECHNOLOGY which can be used and implemnted in simple way because of rich data controls availablity.
Regards