The James Webb Space Telescope will replace the Hubble in about five years. It would be nice if Hubble could last until then, but it's not going to happen, especially with the shuttle out of commission.
Some of the large aperture adaptive optics telescopes are in the same resolution range as the Hubble, so we can get by for a while. There are several other telescopes in orbit as well that operate in different wavelengths. Besides that, there is already more data from the Hubble than astronomers can analyze in a century, and in fact the data is available, some of it anyway, for anyone, astronomer or whoever, to analyze free for the download. Let's use the resources to work on the new program, robotics, back to the moon, that kind of thing.