Another problem with Dimension 3000

This Dimension 3000 has lock up problems. What might be done?

I recently replaced the DELL AIO printer with an HP 1610. I removed the old print drivers and installed the new software. The printer works OK. Now, however, about every other time that I dial in to my ISP the system locks up . The mouse locks and the modem dialer loads but won't dial. I have to power off because ctl/alt/del won't repond either.

Frequent lockups have been a problem using Windows Movie Maker too.

Advice needed.
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