INFO: I'm dealing with Microsoft SQL.
Ok the title is confusing but here's a good example of the table I am dealing with:

ID    Value    Signal    Read    Firmware    Date           Time
5     123      656       444       217       3/30/2009     11:00:00 AM
5     123      421       333       217       3/30/2009     04:00:00 PM
5     123      111       666       217       3/30/2009     05:00:00 PM
9     321      231       551       216       3/30/2009     09:00:00 AM
9     321      599       887       216       3/30/2009     09:30:00 AM

And So I want the Query to come back:

ID    Value    Signal    Read    Firmware    Date           Time
5     123      111       666       217       3/30/2009     05:00:00 PM
9     321      599       887       216       3/30/2009     09:30:00 AM

I've attempted:

SELECT DISTINCT ID, Value, Signal, Read, Firmware, Date, Time FROM ....

But this returns all the results. I've also attempted Choose TOP 1... however i could not have that to operate. I understand this really is simple, but I am confused regarding how to get this display only one single unique row.
Just help.

Perhaps you have attempted this?

SELECT id, value, MIN(Signal), MIN(Read), MIN(Firmware), MIN(Date), MIN(Time)
FROM
  ...
GROUP BY
  ID, Value
SELECT
  ID, Value, Signal, Read, Firmware, Date, Time
FROM
  ...
GROUP BY
  ID, Value

The records are distinct, you will find different Signal, Read and Time values. How does one expect the SQL server to guess which you would like?

Your example indicates that you are thinking about the newest record of the given Id. If that is true, this question should meet your needs:

SELECT table.*
FROM table
JOIN (SELECT Id, Date, MIN(Time) FROM Table GROUP BY Id, Date) AS selector
ON (table.Id = selector.Id AND table.Date = selector.Date and table.Time = selector.Time)
SELECT Id, Value, Signal, Read, Firmware, Date, Time FROM table_name t1 WHERE t1.Id = (SELECT DISTINCT t2.Id FROM table_name t2)

Presuming that there's a cheque to ensure that records with similar Id also provide same return

use TOP 1 WITH TIES

Similar query (uses Mix APPLY and correlated subquery w/ TOP WITH TIES):

SELECT

        a.CustodianAccountNum,

        a.AccountName,

        a.AccountName2,

        a.AccountName3,

        a.AccountStartDate,

        a.AccountClosedDate,

        a.TaxableFederal,

        a.TaxableState,

        qq.ValuationDate,

        qq.MarketValue,

        cg.ClientGroupGUID as ClientGUID,

        c.ClientGUID as EntityGUID,

        convert (bit, case when b.cnt > 1 then 1 else 0 end) as IsDuplicate 



  FROM (

        SELECT      

              a.CustodianAccountNum,

              MIN(a.AccountID) as AccountID,

              count(*) as cnt

        FROM Accounts a



        WHERE

              a.AccountID in (SELECT AccountID from dbo.FnGetFilteredAccountIDs(@CurrentUserID)) -- apply permisssions

              and a.DeletedDate is null



        group by a.CustodianAccountNum

  ) b

  INNER JOIN Accounts a

  ON

        a.AccountID = b.AccountID



  INNER JOIN ClientAccounts ca

  ON

        a.AccountID = ca.AccountID

        and ca.DeletedDate is null

  INNER JOIN Clients c

  ON

        ca.ClientID = c.ClientID

        and c.DeletedDate is null



  INNER JOIN ClientGroups cg

  ON

        c.ClientGroupID = cg.ClientGroupID 

        and cg.DeletedDate is null

  CROSS APPLY 

  (

        SELECT 

              SUM(MarketValue) as MarketValue, 

              MIN(ValuationDate) as ValuationDate 

        FROM

              (SELECT TOP 1 WITH TIES arv.MarketValue, arv.ValuationDate 

              FROM AccountReturnValues arv 

              where 

                    arv.AccountId = a.AccountId 

                    and a.AccountClosedDate is null

              order by ValuationDate desc

              ) q

  ) qq