For Voodoo1 there is no real difference between Win95 and Win98. The Win95OSR2 is from 1997 so I think it's the real deal.
What CPU do you want to use? I like the 110e drivers from diamond.
For Win95 I would use DX5, but if your main gfx-card supports some dx6 features, then go for DX6. (Win98se comes with DX61)
For some software you have to have IE installed (Deamon-Tools, but they require USB support too). You could install IE4 and need not to installe IE5.5.

There are hundreds of great games to play on such a win9x machine. Perhaps you go for a P1-MMX or a Celeron/PII.
If you choose a celeron300 instead of a PII300+ you will still be able to play lot's of dos-games. The P1-MMX will surley play the most dos-games, but
for a hybrid machine, the celeron with the v1 is the better choice. Don't go for a machine >400Mhz because they you will get gfx-glitches with the voodoo1,
especially in D3D mode. Glide will mostly be fine even with CPU>400mhz.

I'd go with Win98 so you can purge the driver easier for a reinstall, should issues occur (with a V2+95 in the day i've definitely had those situations where the drivers corrupt)

Either way is "period correct". Voodoo1s came crashing down in prices in 98 hard making them good budget choices. The official last driver update was around Spring 1999.

Right now, I have the machine running with a Pentium MMX 233, Virge DX 4MB, Canopus Pure 3D and WIndows 98 SE. Was thinking of wiping it and putting WIndows 95 OSR2 on it for period correct as well as the fact I have two other WIndows 98 Machines running as well (PIII-500 and a PIII-Tualitin 1.4) so this would be the Win 95 machine to mess around with, but wanted to see if I was going to lose anything in dropping down to WIndows 95 in terms of performance...so thanks for the info.

On the other end, I am thinking of cutting down on the total number of Retro machines I have up right now to open up some space in my crowded retro area / office from 7 machines and cut down to 1 Win 95, 1 Win 98, 1 Win XP and go from there....