Welcome to the forum. Fellow VX member "TRIATHLETE" is absolutely right in perhaps starting a new thread more pertinent to your question would be best. However; realizing you are brand new to the forum and the nature of your question is tires/wheels, I'll be glad to personally assist you to the utmost of my ability. I've recovered your E-Mail address; so please look for my E-Mail in your computer in-box and we will discuss your topic off-line, so as not to disrupt this particular thread. Again, welcome to Vehicross.Info.
EDIT: After some quick research, these are the closest sizes to the OEM size of 29.5" O.D. for use with a 20" rim.
265/50R20 (30.43" O.D.) - Use this size "ONLY" if you want off-road A/T tread patterns (i.e. Falken Tire Co. & Nitto Tire Co.) - Unlikely to rub.
295/45R20 (30.45" O.D.) - "Street" tire choices only (damn near identical O.D. to above tire, but wider). - May rub very slightly due to width + O.D.
275/45R20 (29.7" O.D.) - Damn near a perfect match for OEM-O.D., but only "Street" tread choices available. - Unlikely to rub.
295/40R20 (29.5" O.D.) - A perfect matching O.D. to OEM., only "Street" tread choices availble. - Although wider, may not rub due to smaller O.D.
If only using "Street" tires on your VX, you may want to consider using taller 22" rims with the following tire sizes close to the OEM 29.5" O.D.:
285/35R22 (29.9" O.D.) - The 285 width will nicely fill-up the VX wheel-wells, and should be bolt-on perfect. - Unlikely to rub.
315/30R22 (29.5" O.D.) - Perfect matching O.D. to OEM; very wide 315 series to give a mean aggressive appearance. - May rub due to width.