A direct answer would be this: your conversion of your IRA from brokerage to Roth IRA will be taxed just the same as your standard income.
This will be determined by the marginal tax bracket you fall under. When you’re continuing to work and have income you’ve earned from said work, it will be a sound choice to postpone your conversion of your IRA until you retire (having less taxable income at that time). However, if your tax advisor proposes that you may be able to convert a portion of your IRA for this year at low, marginal tax rate (e.g. 15% Federal or less), then a partial conversion may be a great option.
Some investors have found that partial conversions that span a period of multiple years can result in the capability to convert a larger IRA to a Roth IRA while at the same time not having to fork over as much to Uncle Sam. For reference, please view the following:
Does a Roth conversion always make sense? (Bankrate.com)
Should You Convert To A Roth? – Forbes
Does converting to a Roth IRA make sense? (About.com)
Take tax control of your IRA conversion (Bankrate.com)
It can be greta to retire in two years, however, you will want to ensure you are as financially prepared as possible for your retirement. If you solely rely on Social Security, and if you only have your $55,000 rollover IRA, you will most likely want to continue working, due to this amount of retirement savings not being adequate to sustain and provide meaningful income for a well-lived retirement.
I do indeed recommend contributing as much as you can afford to your employer retirement account, especially if your employer provides matching contributions.
To close out this Q&A, I do strongly suggest that you contribute as much as possible to your employer retirement account; especially if your employer choose to match your contributions.