The short answer is yes, maybe.
I bet your problem is outside of your SSRS 2005 environment. As @MikeTWebb said, are you sure you are pointing to the right data source? Also, your question is subtle. Have you tried other browsers? You tried in VS2005 Express, which is free and, in my opinion, should be what you should use, not BIDS.
However, the way to do this is quite simple:
SSRS2005 Visibility , , IFF().
, RDL , TableRow :
<Details>
<TableRows>
<TableRow>
<Visibility>
<Hidden>=IIf(RowNumber("table1_Group1") < 5 And Fields!CourseName.Value = "Enterprise",True,False)</Hidden>
</Visibility>
<TableCells>
..etc..
SSRS2005 , , IFF().


, , , , !
, .