Hi Jeff,
Ordinarily, your case should be relatively straight-forward. Your wife will ahve to file a I-130 application (Petition for Alien Relative) with the USCIS, along with some documentation that your marriage is legal. This typically takes a few weeks to a few months to process.
The application costs $185 and should be submitted with the following documentation:
1) A copy of your marriage certificate.
2) If either you or your spouse were previously married,
submit copies of documents showing that all prior
marriages were legally terminated.
3) A passport-style color photo of yourself and a
passport-style color photo of your husband or wife,
taken within 30 days of the date of this petition. The
photos must have a white background and be glossy,
unretouched and not mounted. The dimensions of the
full frontal facial image should be about 1 inch from the
chin to top of the hair. Using pencil or felt pen, lightly
print the name (and Alien Registration Number, if
known) on the back of each photograph.
4) A completed and signed Form G-325A, Biographic
Information, for you and a Form G-325A for your
husband or wife. Except for your name and signature,
you do not have to repeat on the Form G-325A the
information given on your Form I-130 petition.
Here's where you might run into a problem. Form G-325A requires that you list your residence for the last 5 years. It will appear odd that you've not lived with your wife for 25 years. This will likely raise some red flags with regards to the validity of your marriage. You and your wife should therefore consult with an immigration attorney prior to submitting the application.
Wish you the best
solasoy