I have some high quality UGG knockoffs (Emus) that are lined with the nice fleece with a thicker sued (not sheepskin) outer. They do keep my feet warm, but it’s nowhere near worth the money. I bought mine for trudging across through the Midwestern snow and they worked just fine. If you just want your feet to stay warm at home, then geez, just get a pair of slippers. UGGs are $200 and up, and mostly popular as a fashion statement or, to some people a faux pas.
I also saw some cheapo little booties at the store that were knitted on the outside, lined with fleece and had a rubber/foam sole. Those will be warm as well and there’s not fuzzy lining to wear away. They were so cute and under $20. And if by “working at the computer” you mean in an office outside of your house where slippers aren’t appropriate (though I’m not sure UGGs are exactly office-wear either), then you might be better off with thick socks, or I’ve seen a couple shoes lined with fuzziness or knit wool at Walmart, Payless, other department stores.
To summarize, yes, UGGs will keep your feet warm, but they are by no means your only option, especially for the price.