The great debate rages on. My husband anticipates receiving $40-50K from a 401k from a former employer, which he will roll over soon into a self-directed traditional IRA. We plan to invest Foolishly in stock market, of course, for maximum anticipated growth. We've been debating whether or not we come out ahead at retirement by 2 scenarios:
1) converting to a Roth IRA in 1998, paying taxes up front (over 4 years, 28% bracket) and withdrawing proceeds tax-free at retirement, or...
2) keeping trad IRA, have the money we would have paid in taxes and the magic of compounding work wonders, taking a mega tax hit at time of withdrawal. It's hard to anticipate what tax bracket we'd be in then and what our beloved lawmakers will do to the Roth IRA in the future. What approach, factors, formulas, crystal balls can we use to crunch the numbers as best we can with current assumptions?

Also, what portion of the money from the 401k would be taxed upon conversion from trad IRA to Roth IRA?
Thanks!