How much data (rows with 10 columns) can Excel 2000 / win98se /
Pentium I 233mhz (used for point-of-sale) hold and be able to search
and sort fast enough, let's say within max 1sec?

Let's say I have 5.000 products in 1 sheet and an other sheet logs all
sales wich can be 300.000 rows within for 1 year. Can I use sort and
find in the 5.000 rows fast enough to work plesant and can I add
300.000 rows to sheet 2?