Both of the entries you listed legitimate, and it is absoutely fine that they are in your Hijackthis log. Here is some information about WgaLogon
It is related to "Windows Genuine Advantage", which basically means that it makes sure that the version of Windows you are running is legitimate; Microsoft have recently been quite heavily targeting pirated versions of their Operating Systems, not providing updates or software for them etc. This used to be vountary (checking if your OS was 'genuine') but it has recently been made mandatory. So, this entry is perfectly safe to have in your HijackThis log.
entry is a part of MSN Messenger, which we can tell from the "C:\PROGRA~1\MSNMES~1", which is a shortened form of C:\Program Files\MSN Messenger
. Here is some information on this entry, although it isn't particularly in-depth:http://www.liutilities.com/products/wintas...ibrary/msgrapp/
The fact that this file is listed as "missing" is actually wrong; this is one of only a few files that is incorrectly listed by HijackThis. This is explained at CastleCops here
, which, since you say you often research the entries in your HijackThis log, is an excellent place to look. It is one of the lists of entries that helpers swear by due to their huge databases, and it is an excellent resource for you to use too.
So, there is nothing to worry about with these two entries.
However, if you'd like to to take a look over your whole log just to make sure it's clean, post it back in your next reply and I'll check it for you.