I have opened ROTH IRA account in 1998. I found now that my MAGI is > 50,000.00.
What are the option do I have now?
Since, my company has 401k plan I can not open regular IRA. Can I open regular
mutual fund and transfer the money?
What do I need to do to report to IRS?
Any extra IRS form need to fill out?

I'm confused by your question. Since you have earned income and your MAGI appears to be less than the maximum $95,000 for single filers and $150,000 for married filing joint return, I can only assume you mean you're not eligible because you are married filing separately? If this is the case, you are not eligible to contribute to a Roth with MAGI over $10,000 and you are not eligible to convert to a Roth at all.

To correct the matter you can recharacterize your Roth to a traditional IRA. Even if you are an active participant in a plan at work, you may have a traditional IRA (as long as you're under 70 1/2 that is). The question then becomes whether you can deduct your traditional IRA contribution on your Form 1040 (doesn't sound like it) or you have to report it on a Form 8606 as nondeductible. Either way, you get the benefit of tax-deferred growth in the IRA until you withdraw it.