If I understand you correctly, you want a list of all the names regardless of which table they come from, correct?
In Crystal 8.5, there is an option to edit the SQL that Crystal generates. You'll need to take this option and do a query similar to the following:
Select "Table1"."Name", "Table1"."LastName
from Table1 as "Table1"
Union
Select "Table2"."GuestName", "Table2"."GuestLastname"
from Table2 as "Table2"
The data from both tables will come through with the field names from the first table. You may have to tweak the query a bit to get it to work - I haven't worked in 8.5 in a number of years so I don't remember exactly how it wants things set up.
-Dell