gwen etymology

Hi, I just joined today. Love languages, linguistics, mythology,
etc., and am currently working on getting a degree in ling. Anyhow,
I
was wondering if any of you could help me out on a particular
etymological problem I'm having. =)

I'm currently doing a little research (a bit for a class, but mostly
out of personal curiosity) on the IE *gwen. I'm hoping this will
turn
out alright once formatted - if not, please forgive me.

IE *gwen- woman
IE *gwen-a- woman? (suffixed form)
IE *gwen-i- woman? (suffixed lengthened-grade form)
IE *gwn-a- woman? (suffixed zero-grade form)
Common Germanic *kwen- woman
Old High German cwán/quina woman/wife/queen
Old Norse kwaen woman/wife/queen
Old Norse kvinna/kvenna ?
Old English cwen woman/wife/queen (from *gwen-a-)
Old English cwene woman/prostitute/harlot (from *gwen-i-)
Middle English quene woman/prostitute/harlot
Modern English queen queen
Swedish kvinna woman
Icelandic kona/kvennmaor woman
Faroese kona woman
Danish kvinde woman
Old Dutch quene old cow/barren cow
Dutch kween old cow/barren cow
Frisian kwyn old cow/barren cow
Gothic qino woman
Gothic qens wife
Common Slavic *z'ena woman
Belorussian z'ana woman
Bulgarian/Polish/Slovak/Serbo-Croatian/Slovene/Cze
ch/Ukrainian/Russian
z'ena woman
Sorbian (Wendish) z'ona woman
Old Greek gunh- woman (from *gwn-a-)
Modern Greek gunaik- woman/wife (from gunh-)
Modern Greek gunaio tart/jade/strumpet (from gunh-)
Sanskrit jani wife
Sanskrit gana/gna woman/goddess
Common Celtic *ben-/*bena- woman
Old Irish ben
Modern Irish bean
Modern Scottish bean woman/wife
Scottish queyn queen
Modern Welsh benyw wife
Cornish benen wife
Manx ben woman/lady/wife
Persian zan woman
Persian/Kashmiri zanana woman (from zan)
Phrygian bon-ekos wife (with a suffix)
Armenian kin/gin woman/wife
Tocharian A s'än woman
Tocharian B s'ana woman

The problems I'm having: In some reference materials I've looked in,
it says that in Sanskrit, "gana" means "woman", in some it says
"gna",
and in others it says "gani" - and in with the latter two, it often
says "gana" means either "song" or "cast". Any ideas as to which one
is correct, or which is/are more correct? Also, I couldn't find the
J
letter/grapheme in the dictionaries anywhere - I thought Sanskrit had
a J and pronounced it the same as PDE? At any rate, I couldn't find
any information on "jani", so I don't know if that's supposed to mean
"wife" or not. Could someone please explain any of that to me, and
how, if "g*n*" and "jani" are related, why they differ so?

Further, could someone explain to me certain sound changes that
occurred from the "gw" onset in IE - to, say, the "z" in Persian, the
"s" in the Tocharian langs/dialects. I can somewhat see how "gw"
changed to "b" and so on, but even though I don't know many of the IE
sound-change laws, the s/z thing just seems strange to me.

I find it very interesting that from the original IE meaning of
"honoured woman", in some of the languages amelioration occurred,
making it more of "goddess" or "queen", and in others pejoration
occurred, degrading it into "hussy"/"cow"/"harlot" etc. Apparently
English developed two words from the same basic root in order to
distinguish between the two distinct meanings. It could all bring up
some lovely historical social commentary. =)

Also, OT, I was wondering about the Welsh name Cai, as in Sir Kay and
such. I'm assuming it's related to the Latin Caius/Gaius. Please
correct me if I'm wrong, but wasn't the "ai" in Latin pronounced /e/
early on and later changed into sounding like their "ae", /ay/? The
Welsh Cai is pronounced /ke/, right? Did they change the sound of
it,
and if so, why didn't they just stick with the /kay/ sound when the
Romans brought the name over? I'm probably way off here, but
nonetheless very curious. Further, what did the name mean in Latin?
I've heard various sources claim it meant "man" (as in the slangish
PDE "guy"), some say it meant "happy", etc. Would be interested to
know that as well.

Thanks a bunch, and sorry for the massive post.

- Eris