OK, why not, good luck. Sorry I wasn't more help.
I don't have much experience with XP on anything but fairly fast machines, so my advice is worth what you paid for it or even less! People tell me the amount of ram makes more difference to it than cpu speed. I do run Windows 2000 on a 500MHz machine with 384M of ram and that performs well for what I do with it. On the other hand for photo editing I use the Gimp on Linux on a 1.6GHz machine with 1G of ram and for that I doubt I'd be happy with much less.
If buyers have sense they ought to be interested in your auction -- if you search for Toshiba on this site there's a depressing number of 0 rated sellers offering stuff, whereas you have good feedback. There's no way I'd send hundreds of quid into the ether in the hope of receiving a laptop from any of those people with no track record.