What do with wife's pensions

[Jefferson Steelflex]

My wife (39, low rate tax payer) recently changed jobs, and as yet has not joined the new company pension scheme (which is one of these very basic 1% jobs). She has two frozen pensions from prior jobs, one with Scottish Widows worth only £3500 and one with Aviva worth about £12k.

As a fairly low earner, only paying small tax amounts as her monthly earnings chop and change, we are not sure how to approach her future pension plans. With the personal allowance, and an allowance for business miles built into her tax code, she will probably pay less than £200 in income tax in the whole year.

I'm advising her to combine the two dormant pensions into one (although one of the pensions companies is blocking this because of the low transfer value), and then look into the forthcoming Retirement ISA (?) but i'd appreciate some advice on whether there is a better investment vehicle for a lower-rate tax payer with 21 years to retirement (retiring at 60).

Also, any advice on what to do with the existing pension pots?

Thanks....