Do any conservative Baptist churches recognize infant baptisms despite not performing them?

The issue that Baptists have with infant baptism is not the form, it is the consent and understanding of the person being baptized. They would say that a person who has not personally understood Jesus' sacrifice, repented and made a personal commitment to follow him, is not a Christian and so cannot be validly baptized. Infants cannot understand their salvation or personally decide to follow Jesus, so an infant baptism is not a "valid baptism incorrectly done".

Having said that, there are Anabaptist (Mennonite) churches considering admitting those baptized as infants, but no Baptists that I know of. However, in Protestant Christianity it's never safe to assume that no group believes any given thing.

I think you would be hard-pressed to find any Baptists who "recognize" paedobaptism if by recognize you mean that they believe it is a valid and biblical practice. However, there are many denominations who distinguish between "essential" and "non-essential" doctrines. The essential doctrines are those that are essential to the faith so that to deny them is to deny Christ and they would not allow a person into church membership who did so. Non-essential doctrines, on the other hand, are doctrines on which Christians may disagree in good faith and still remain in fellowship and membership in the same church. There can be great variation in what a given denomination or individual church would define as essential, although virtually all conservative, orthodox or evangelical churches would consider doctrines such as the Trinity, the two natures of Christ, the Atonement, and the physical resurrection of Jesus essential.

When it comes to Baptism, things get more complicated. There are some who consider Baptism essential while others do not. This tends to come down to two factors. First, what role do they believe that Baptism plays in Salvation? Some Denominations see Believer's Baptism as necessary to salvation (Church of Christ for) or teach Baptismal Regeneration (some Lutherans), while others see Baptism as an obedient action or parental sacrament. The greater the role one believes Baptism plays in salvation, the more likely they are to consider it essential

The other factor is denominational. There are some denominations that consider Baptism essential. A church that is a part of a denomination that does this is much more likely to consider it essential as well. There are other denominations, however, that not only do not view it as essential, they do not have an official position on Baptism (Evangelical Free and CCCC, where I'm a member, are some examples). In these denominations each church (or pastor) is free to determine their own view of baptism. In order to maintain denominational fellowship, those who adopt a Baptist view must still be open to fellowship with other pastors and churches who do not and are, therefore, much more likely to accept those who disagree into membership. But even some denominations that are specifically Baptist view it as important, but not essential. For example, many Reformed Baptist churches hold this view and have many members from Presbyterian or Dutch Reformed backgrounds who are welcomed to join the church without being re-baptized. But even in the SBC (in which I grew up) you will find some churches that allow a person into membership who holds a paetobaptist view. Since the SBC believes in the autonomy of the local church (http://www.sbc.net/faqs.asp), there is no requirement that Baptism be a part of membership standards and any SBC church that views Baptism as a non-essential doctrine is free to admit members who were only baptized as infants.