I have managed to get on-line at home! It appears that the problem was with my router and not the computer at all. Which means I screwed my computer up for nothing. 
I've got the computer going straight to the cable modem at the moment. I'll get the router figured out later.
I got partway through the mamoth task of un-messing everything this afternoon. I was pleasantly surprised to find that some of the programs were still working (e-mail, rss, trillian) others are installed but need to be set up again (winkey) a couple seemed to need to be re-installed, but once I did they remembered their old preferences files (walleyes) so I didn't have to go back through the humongous task of setting that up all over again. Re-installed Exel and Word. I loaned my copy of PhotoShop to a friend so I'll have to wait till I get the disk back before I can get that back up and running. But for the most part it seems that I didn't mess it up as badly as I feared. Which makes me a very relieved Suni! 