1N4007 comparable with 1N4001 diode?
Yes. The 1N4007 can withstand a higher reverse voltage(\$V_r\$), 1000V vs. 50V. The 1N4007 may even be a better choice, esp. if your motor is powered by a voltage near 35V. (The 1N4001 is rated for a \$V_{r(RMS)}\$ of 35V.)  

While diodes like 1N400x may be well suited as freewheeling diodes in terms of voltage and current (rated at 1A), they're not exactly fast. To protect your transistors Schottky diodes would be a better choice, but they usually have limited \$V_r\$.  

Here's the \$V_r\$ for the 1N400x series:  


  1N4001: 50V
  1N4002: 100V
  1N4003: 200V
  1N4004: 400V
  1N4005: 600V
  1N4006: 800V
  1N4007: 1000V