Unfortunately I don't have a simple solution for you. You cannot import the application to Access, only the data tables. When you do this you will lose any coded relationship between the tables and you will need to re-establish any look-up links or data formatting restrictions. All reports, queries and forms will be gone and must be recreated in Access. If you use an access programmer for this, he may be able to glean some information from the *.sc files in your applications directory.
You might be able to buy an old copy of 4.x (DOS), which would allow the application to run on your Win98 machines. You may have to hunt EBay to get it, but it should be very cheap. Your system guys should be able to set the shortcut up so that it runs full screen. If you have trouble with Paradox for DOS, the best guy to ask is Steve Green (
http://www.diamondsg.com/main.htm). He may even have a solution for your version 3.
When Paradox went to a Windows version the programming language and structure changed dramatically, and none (or very, very little) of your Version 3 code is compatible with the 'modern' version of Paradox.
Hope this helps,
Mac