Windows 3.1 uses less resources, so it'll be faster, but Windows 95 will run newer apps. Although, I suppose the age of the apps shouldn't matter much, as both 95 and 3.1 will have some really really old apps, and would only be marginally useful online. (NT4 is where it's at, for retro Windows productivity. )
I'll have to try that some day since I recently got a machine that'd be good with Windows 95 -- it'd be similar to running it in VPC on a 1400 (if not faster, this is a P120 with a 1.2 gig hdd, and I can upgrade it to 40 or more of ram.)
If one shows up at an affordable price on eBay, I might get a G3 accellerator for the 1400. Although a floppy drive is still my top priority.
Speaking for floppies, I just bought two packs of 10 coloured HD disks . I've never had coloured disks before (except DD ones which I use on the Amiga).