I won't duplicate web content on what it is short of it's part of Vista Media center to create thumbnails or such. This will run for days as it scours your machine for video to work on.
Your choice on what to do or let it finish.
eMachine - W5243
AMD Athlon 64 Processor 3800+ 2.40 GHz
2gb Ram 32 bit OS
NVIDIA GeForce 6100 nForce 405 video card
Video Bios ver 22.214.171.124.01
Available graphics 831mb
Western Digital WD25 SCSI Disk 250gb
USB STECH Simple Drive 500gb
USB Maxtor OneTouch 650gb
Vista service pack 1
Just in the last week, I've experienced issues with Media Center. When I open up "Recorded TV" the list appears of all the items I've recorded. If I select one to watch it engages "ehvid.exe" and hogs anywhere from 75% to 98 % of the CPU. The show never comes up. I manage to, eventually, return to the previous page. But "ehvid.exe" never "turns off" and continues to hog the CPU. I've since learned that if I can get TASK MANAGER to come up, I can END PROCESS of the ehvid.exe and get control back, until I go back into Media Center.
I saw on another techie page where someone recommended to uninstall the October cumulative upgrade for Media Center. For him and others he knows, this fixed the problem. For me it did not.