Thanks for the replies. All those Visual C++ together are not taking up a lot of space and my system is pretty stable. It is best to leave them alone.
This is what I found in worldstart.com:
So why are there so many of them on your computer? New C++ libraries become available over time, and there are different versions of each year’s release. The new ones don’t “overwrite” the old ones, however, meaning there may still be data in the older version that programs need to access, and deleting them can prevent those programs from working.
There isn’t a simple and sure-fire way to know which program is using which redistributable version, and you may even have several different software programs all using the same C++ file, so frankly deleting old ones to save a small amount of hard drive space isn’t worth the possible risks.