fix computer errors

way back i restored the system in veiw of unnecessary updates that got into my sys.the system restore points were available only at that days when i installed new softwares.i restored the system and found that most of the softwares were gone and even the internet explorer setup module was also missing…..so i restored the sys again.in short “UNDOED” that ..and then the problem started …most of the softwares were not there….so i tried to reinstall them ..but i could’nt …every time i do get an error….by updating my sys to INTERNET 7 i could access the internet…but the internet based search softwares donot work…like ARES…can any body sort this thing out?