Ida is the name of a galaxy that was home to the Asgard. At one point, the Ancients also inhabited space in the Ida galaxy or may have been made aware of the Asgard by way of the Destiny. The galaxy is approximately 4 million light years from the Milky Way. (SG1: "The Fifth Race", "Enemies")
The stargate seen on Othala seems to be a second generation stargate, the same type found in the Milky Way. Which suggests that the Ancients explored and seeded the Ida galaxy long before the Pegasus galaxy.
Based on the stargate address for Othala, the galaxy is in or near the constellation of Scutum. The possible candidates (i.e. lying approximately 4 million light years (Mly) from the Milky Way) are: Sextans B (4.44 ± 0.23 Mly), NGC 3109 (4.3 ± 0.3 Mly), Sextans A (4.31 ± 0.13 Mly), and Antlia Dwarf (4.31 ± 0.20 Mly). All these 4 galaxies are on the other side of the local cluster compared to the Pegasus galaxy.