If i may reccomend:

1. Coocked one - Energy rom/Near the stock Ark_n rom
2. Coocked one - leo Cell rom/Near the stock athine/

This roms are the best. I cant make my mind between Energy and Ark. Well to be honest, I need 4 tp2 phones to run them all.

There are allso other like, e2, Deep shining, josh ... and others.

Try manila 2.5 21898 roms, thay are with win 6.5 (like yours).
23xxx rom is with 6.5.x windows mobile.
I didnt try 23xxx bild.

there is posibility of dual boot android and winows... but i dont know nothing about it.

Good luck