First, A LOT is two words. Second, you don't 'tape' things on the DVR. There is no tape. But anyways...
No, you should not be having that many screw ups. Every now and then, yes. But it should be the extreme exception and not the rule.
Did you get a new television or hook up anything new via HDMI cables? My 722k would not record properly with the Logitech Revue connected via HDMI nor would TV2 out work worth a you-know-what. As soon as I removed the Revue, all the problems were gone.
You might try running a diagnostic to see if there's anything the DVR can detect. If the DVR reports everything 'normal' than it's either something the DVR can not detect or something else in the system is bad or going bad... Remember to consider parts on the dish outside, any switches you have, and cabling. (One time I was having all these intermittent problems and it turned out that the power supply to the DPP44 switch was going bad... Dish sent about 3 replacement receivers before they would listen and decide maybe it wasn't the receiver.)
Good luck. Keep us updated.