Oil Experience

This is not a question about my truck per se but about oil in general, this oil being in a car I inherited.
I have never experienced this and the forum for the make of this car is like a ghost town.
I pulled the valve cover in this car to check out valve noise and immedately smelled burnt oil, no gunk no crust just oil that smells like someone put a torch to it, or like it leaked onto the exhaust.
The oil is black and ovbiously needs to be changed, but since I have never let my oil go that bad so I am not sure if the burnt smell is just from being old or what, there is no fuel coolant or anything else foreign in the oil that I can tell.
The clattering seems to be from a couple of collapsed hyd lifters, and though there is oil leaking from the cam oil journals when I pulled them it looks like it was starting to eat the cam bearings with a slight groove inline with some of the oil journal's on the cam.
Could all this be from just not changing the oil? I didn't know the previous owner very well so I don't know thier habbits but I have never known a person that didn't change their oil at least once in awhile and never seen or smelled oil like this "in" an engine.
I would appreciate any kind of input on this I can get

Really would like to know what vehicle here for starters. For 22 bucks you could have the oil analyzed to see what is happening. If this an an ohc engine the cam journal issue is a bad sign.

Thanks for responding maxwedge, I was considering pm'ing you about this but went ahead on the public forum instead.
I was looking to possibly hear from service techs that encounter really abused cars, and though I usually post according to the make of car as I should the tech's I have encountered on this and the chev forum have earned my respect and in my opinion are some of the best on A/F as a whole.
The car in question is a mazda 626 w/a 2.0 with dual overhead cam's, a ford mazda crossover with the probe being it's mirror.
I get no response from the ford people on my post's and the 1 lone mazda responder was quite nice but suggested a motor swap when I posted about the bad lifters, overkill to say the least, in my opinion.
I figured the cams were toast as well and since these engines have no replacable cam bearings so is the head, I have already scoped a new head on ebay for it at $200.00 cams lifters and all.
But really my question/concern is not so much about the mechanicles but the oil, it's condition and cause.
In all the makes of cars I have ever worked on in ore than 20 years some with more than 10k on the engine oil I have never smelled such a burnt oil smell when opening an engine and was wondering if simply not changing the oil for a very extended period of time could be the cause of this, as well as could this be the cause of the cam bearing failure, I figure it is but just looking for a little confirmation.
What other possible causes could there be for the burnt oil smell in the engine is my main question I guess.

Any metal part in the engine that fails as a result of scoring and lack of lube creates heat that is transferred into the oil, everytime I spun a bearing in my race car the oil had the smell you describe. I would be real careful here about fixing this engine unless I took a look at the crank and bearings, you may just be seeing the proverbial " tip of the iceberg".

Thanks again for the response maxwedge, I did consider the main and rod bearings might have sustained the same sort of damage but have tried not to think about it, the head and cam caps are aluminum with the damage very slight so I have hoped that the harder lower end bearings were spared any severe damage.
I don't really want to make this one into too much of a project just a couple of months winter beater then off to a pick/a/part as a re'builder since the body and interior are in great cond, all I have into it is the tow to my property so far and really don't want to put a whole lot more into it.
When I dump that funky oil I will pull the pan and one of the rod and main's just to have a look see.
Thanks for the info on the smell, I never noticed it in the past but I was a heavy smoker and may not have been able to.
Thanks again for your input I really do appreciate it.