I've read hundreds of these type of threads, where Windows 7 was installed as an upgrade over Vista, rather than a clean install. Without seeing the PC, I don't know if this was done. But I do know that in most of the instances where Vista was upgraded to 7, there was almost guaranteed problems. Once most of these users clean installed their computer with Windows 7, having the proper drivers, the problems went away.
BSOD's, freezing, all sorts of issues with upgrade installs. And I doubt that MSE is the problem. While I no longer push MSE, I can say that it's very computer friendly, on XP, Vista & Windows 7.
Seems like this "tech" would know how to do a clean install with upgrade media. It's no secret, it's been known for over 2 years now. Paul Thurrott done a tutorial on his SuperSite, sort of a walkthrough on doing it. Several other writers basically re-wrote the same article, it's the same.
How long ago was it that the tech done this install? If it was recently, he/she should stand behind their work, if it's a reputable place of business. If so, take it back, report the issues, & ask for a clean install, if it wasn't done as such from the beginning.
And did you get install media with your upgrade? You should have the install disk, and there should be a Windows 7 COA (sticker) on the bottom, side or back of the computer. If it's a notebook, it'll be on the bottom.
EDIT: Couldn't find Paul's tutorial, he must have included it in a book. But here's another on how to clean install Windows 7 with upgrade media, on a formatted or blank hard drive:
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Don't know if it's too technical for you, but I took the time to search anyway. This is the best link that I could find.
Cat