Margaret MacGregor is not a computer expert by any stretch, but the 78-year-old Neenah woman is finding a new career on the Internet. She dispenses advice through Ask Grandma in a small corner of the World Wide Web. MacGregor responds to readers' questions and writes a column about enjoying life in the later years as part of a web site design by her grandson for his wife's Minneapolis elder care consulting business. Grandma's column often doesn't directly relate to housing issues. In the couple of months she's been writing Ask Grandma, she's covered such far-flung topics as dating after losing a spouse, the importance of making out a will and the joys of having a pond in your back yard.