Two questions in one...
I have not heard it described as "delayed" trades... so I'll talk about the two main types of "buy" trades... Market and Limit.
When you place a trade in WSS using "Market" for the "order type", the trade is placed immediately at the real time price of the stock. The delayed price you see is the price it was about 15 minutes before you placed the trade, and sometimes it happens to be the same. If they are the same and you do not have R-T pricing in WSS, then it is a coincidence. 
If you use "Limit" for the order type, then the trade goes through at the price you set ... or, with a bit of luck, maybe even a little better. So the time of a LIMIT order depends on when your price is met.
I think the first one is what you wanted, but covering all bases just in case...
