First, you've got my sympathy! I love my XP box!
Second, some actual advice.
If you're looking for installation help, don't install to C:/Program Files/EA Games. Install to C:/EA Games instead. Same goes for utilities, which should be installed to C:/Sims 2 Utilties or the like. This bypasses the "nanny state" protections on C:/Program Files.
If you've already installed to C:/Program Files, you'll have to deal with the nanny state on an incident by incident basis.
Modifying text files or creating zip files: Most text editors and compression utilities can't handle saving to C:/Program Files; to modify a text file located there, you'll need to save your files elsewhere, such as Desktop or My Documents, and drag them to the correct location. Same goes for making zipped backups of files you're going to delete using my No More Ugly Maxis Created Townies tutorial or BoilingOil's Keeping Your Sims 2 Installation As Small As Possible tutorial.
After dropping the dragged file, you may be prompted for an administrator password if you are not logged into an administrator account.