My $0.02:
Digital scopes, analog scopes, and logic analyzers are different tools. It's like a screwdriver, pliers, and a hammer. In a pinch, you can make them do things outside their comfort zone, but the best option is to have all three.
I do digital stuff and use my Rigol DS1102E. I love it, but do wish you could have more measurements on-screen at once. (Limited screen area.. what can you do?)
I do analog stuff and use the Rigol there too. It's clearly out of its element, and when I cross paths with a Tek, I'll snag it.
I do multi-channel digital, when the timing of events is more important than their exact waveform. The Salae 8-channel logic analyzer is a wonderful tool. It would take a powerful and expensive scope to be a decent logic analyzer, while you can get an actual LA for not much money.
OP: Get a new computer. If you can afford $3-500 for a scope you have no excuse to keep beating a 486 into submission. You can pick up a motherboard or mini pc or netbook for peanuts. 
No USB 2.0? C'mon man, there's no good reason to keep using that thing.