The "girly seat" looks to me like a sella san marco rolls which is quite a nice saddle and not made for girls or in any way what I would consider girly. I have been wanting a white one for a bike I'm putting together, but they're kind of expensive generally. It is a sweet find especially for free, but I would say leave it complete because it seems fairly original, which even though that bike isn't really very collectible (though it is a very nice bike) is pretty cool. If you do make it a single speed definitely don't cut anything off like the derailuer hanger and it would be good to keep all the parts together in a box or something so you can put them all back on if you want. If you do that its just a matter of a couple hours work if you want to make it original again.