Thanks for the responses. (and the welcome too
I bit the bullet and a repair box is on its way. Not worth the frustration anymore and it was eating at me while I shouldve been focused on house projects etc.
On the HD, I had gotten so frustrated yesterday that I bought a memory card transferred my saves, gamer profiles, etc and reformatted it twice in a futile effort for things to miraculously correct themselves(well i was hoping it was a fragmentation issue...). It didnt make a difference, COD 2 still stuttered. One lesson learned along the way (the hard way), is that if you have a premium system, Hexic HD doesnt even appear to be a Marketplace download, so if you ever erase it, its not like other purchased content, its gone. I need to follow up with MS to see if I can get it back later, I just thought it would be attached to my profile like other XBLA purchased content... it isnt, bad assumption on my part. There must be a way.
They are also replacing my HD cause that seems to be at least one of the issues. Since I already wiped it, there is nothing more to lose. Personally, I think its probably more an issue of the console itself talking to it, than the HD itself, but better safe than sorry(and realistically.. what do I know...?).
I just hope their diagnostic program picks up that my DVD is fubar. When it works, it partially works, it just there are usually 2 or 3 issues along the way every night (not recognizing the disc, trouble accessing data, etc etc)
So I guess middle of next week the box will arrive and the "360 with known problems" will return in 2 weeks as the "360 of the unknown" Oh well, its a good break. Maybe I'll either get some good house project work done or go back and finish an XBOX1 game or two I left behind.